Space Lasers: Aiming Towards Next Leap in Global Communications

By Rick Williams, Kaman Precision Products

Space lasers are transforming the world. Not the far-off future of science fiction, but the universe of how data and communications flow today — everywhere from deep space missions to countless applications here on earth, including consumer internet services, military operations, and banking transactions.

Lasers can transmit vast amounts of data over great distances at the speed of light, 100 times faster than previously possible in space. The narrowness of the light beams makes laser communication remarkably efficient. The highly focused light is aimed at the receiver, resulting in minimal beam divergence and signal loss and allowing for reduced power consumption.

Staying on Target
Indeed, this narrowness of the laser beam also presents daunting technological challenges. In space laser communications, impeccable precision is needed to align transmitters and receivers across vast distances as the terminals move at varying speeds and directions — a level of accuracy comparable to hitting a three-point basketball shot from 100 miles away.

Engineers have addressed these challenges by developing fast steering mirrors (FSM) controlled with extremely sensitive sensors. These systems keep the beam precisely on target for satellite-to-satellite and ground-to-satellite links and deep-space communication, facilitating accelerated growth in the flow of data around the globe.

For all its benefits, optical communications still face several challenges. Unlike radio communications, which can be sent out in a broad beam blanketing target areas with its signal, optical communications are sent in a relatively narrow beam pointed directly at a receiver. When broadcasting from thousands or millions of miles away, an optical communications telescope pointing must be extremely precise. A deviation of even a fraction of a degree can result in the laser missing its target entirely.

The Galactic Network
These capabilities — laser communications with FSM tracking — are bringing us closer to what might be called the “Galactic Internet.”

That was the imaginative term coined in the early 1960s by J. C. R. Licklider, the first director of the Information Processing Techniques Office (IPTO) at the Pentagon’s ARPA, to describe the possibility of a digital “network” open to all that would serve as “the main and essential medium of informational interaction for governments, institutions, corporations, and individuals.”

ARPANET became the first wide-area packet-switched network with distributed control and proved instrumental in shaping modern computer networking and the internet.

Copper Couldn’t Satisfy the Insatiable Demand for Bandwidth
In the early days of the internet, most data was transmitted over copper cables, taking advantage of ubiquitous telephone networks. However, electrical transmission over copper suffers from signal attenuation due to resistance in the conductor and dielectric losses.

As the internet evolved from text-based emails to images, videos, and games, the standard 56.6-baud dial-up modems became obsolete, and internet service providers (ISPs) and backbone networks needed new transmission methods to keep up with the tremendous surge in data traffic.

Fortunately, as computer scientists were creating the internet, the field of photonics was developing a method of using light to transmit data much faster and over much longer distances than what is possible with electricity conducted through copper wires. 

Fiber Optics Enabled the Growth of the Internet
The first continuously operating helium-neon gas laser was demonstrated in 1960, and a decade later, scientists at Corning Glass Works invented ultra-transparent glass that could be mass-produced into low-loss optical fiber. By 1977, fiber optics began to carry traffic over public telephone networks. and in 1986, Sprint deployed the first nationwide 100% digital fiber-optic network.

Optical fibers can transmit up to 60 Terabits per second, more than 700 times faster than copper. And the data quality is superior because the optical signal is not subject to electromagnetic interference and radio-frequency interference (EMI/RFI), crosstalk, and impedance problems that cause signal distortion and loss with copper.

A watershed moment came in 1986. The invention of the erbium-doped fiber amplifier (EDFA) significantly increased the distance an optical signal could be transmitted before requiring an electronic repeater, making fiber optics practical and economical for intercontinental undersea cables. Previously, submerged copper cables operated at only 140 megabits per second and required powered electronic repeaters at frequent intervals.

The first transatlantic fiber optic cable went into operation in 1988 — a year before Tim Berners-Lee proposed what became the World Wide Web, causing a further explosion of internet traffic. Today, submerged optical cables carry 95% of the world’s data traffic. Each single fiber has a bandwidth in excess of 1 terahertz, one thousand times greater than what is possible with copper wire.

Free Space Optical
Fiber optics enables significantly higher data transmission rates, over longer distances, compared to copper wire. But fiber optics is limited by the length of the strand of fiber. What if the benefits of optical data transmission could be untethered from this physical limitation, extending thousands of miles through space?

Laser communications, also known as Free Space Optical (FSO) communications, utilizes much of the technology developed for fiber optics to wirelessly transmit data through air, vacuum, or outer space. FSO is reliable over vast distances when the light propagates in space for inter-satellite and deep space links.

Over the past five to ten years, satellite cost performance has, in some instances, improved more than 1,000 times, and satellites produce and transport much more data than ever before. There are few parallels for a disruption of this magnitude, except the transition from mainframe to desktop computing in the 1970s and 1980s.
McKinsey & Company, The role of space in driving sustainability, security, and development on Earth, May 2022

Unfortunately, here on Earth, atmospheric factors such as fog, rain, dust, heat, and even birds pose significant challenges to Free Space Optics (FSO) technology. These factors lead to signal failures and unacceptable error rates and limit the feasibility of long-distance point-to-point optical links between terrestrial terminals.

In the early 2000s, companies like Terabeam, AirFiber, and CableFree invested significant sums in FSO as an alternative to fiber optics. However, none of these ventures could overcome the challenges posed by atmospheric conditions to establish commercially viable services.

Terrestrial laser internet service is experiencing a resurgence, with deployments in 13 countries, including Australia, Kenya, and Fiji. In June 2023, Alphabet, the parent company of Google, unveiled its ambitious plans for large-scale implementations in regions of India and Africa, where fiber optics is difficult to deploy, aiming to provide up to 20 Gbps bidirectional throughput within a 20 km range.

Space Lasers Vastly Outperform RF
These distance limitations do not exist in the “free space” beyond the Earth’s atmosphere. Lasers perform exceptionally well over great distances, in the vast emptiness of space, far more efficiently than what is possible using radio frequencies (RF).

Before the advent of FSO, all communication in space used radio and microwave bands, regions of the electromagnetic spectrum with the longest wavelengths and lowest frequency.  NASA beamed TV signals from the moon using the S band (2–4 GHz), and later the X band (8–12 GHz) and the Ka band (27–40 GHz) provided faster transmission rates. NASA’s Deep Space Network currently achieves speeds up to 50 Mb/s with the Ka band.

No More RF Red Tape
Before you even start thinking about launching your satellite you need to apply for a license from every country you want to send an RF beam down to. You have to pay the costs associated with each licensing regime. Then you have to wait. And wait….
Laser communication is not regulated by the International Telecommunication Union and it can be used without restrictions and does not require costly licenses. The reason for this is that its inherent small beam size avoids interference issues and renders any restrictive regulation in the future highly unlikely.

The low transmission rates are not the only disadvantage of RF: radio signals spread out as they travel, causing two additional problems. The first is the overcrowding of the RF spectrum which causes the overcrowded RF airwaves causes interference, interception, or jamming, and the scarcity of available spectrum severely restricts the expansion of services.

The second problem is that beam divergence causes significant attenuation of the RF signal. The farther the distance, the weaker the received signal. To compensate, transmitters and receivers are enlarged, and power consumption increased, placing costly demands on satellites and spacecraft. RF ground stations have antennas as large as 230 feet (70 meters) in diameter.

Advantages of Space Lasers
Laser communications offer an effective solution to these challenges and limitations of RF.

Bandwidth – The primary advantage of laser communications compared to traditional RF signals is a dramatic increase in bandwidth. Space lasers use non-visible infrared radiation (IR) portion of the electromagnetic spectrum has frequencies ranging from about 300 gigahertz (GHz) up to about 400 terahertz (THz). The higher the frequency, the more data is encodable in the waveform, resulting in effective bandwidth increases of 10 to 100 times compared to RF.

Low Latency – Faster doesn’t just refer to the increased data transmission per second. Laser communications also achieve a significant reduction in latency with near-instantaneous data transfer with delays 10-20 milliseconds, compared to the hundreds of milliseconds experienced with RF.

No Spectrum Congestion – The short wavelengths (less than 0.1 centimeters, compared to RF wavelengths of 0.8 to 15 cm) and the highly focused beam frees FSO from the many headaches and limitations of spectrum overcrowding. Laser communications links do not interfere with each other, and therefore the possibilities for expanding FSO in space are practically unlimited.

SWAP – Another important benefit of the tightly focused beam is that laser light does not spread out the way radio waves do, allowing optical signals to maintain their strength over great distances. Less beam divergence and attenuation mean more of the transmitted power is captured by the receiver and less power is wasted. According to NASA, “optical communications provides decreased size, weight, and power requirements. A smaller size means more room for science instruments. Less weight means a less expensive launch. Less power means less drain on the spacecraft’s batteries.” These benefits extend to equipment on the ground: laser communications receivers can be up to 44 times smaller than current radio antennas.

Security – The narrow beams also make laser signals extremely difficult to intercept. Moreover, space lasers use light and photonics, and therefore Quantum Key Distribution (QKD) can add unmatched levels of security to these communications.

Revolutionary New Services
During the era of RF space communications, most data traffic heavily relied on geostationary (GEO) satellites. Positioned at an altitude of 35,786 km (22,236 mi) to maintain fixed locations above the equator, these satellites offered stability and efficiency by ensuring coverage across a significant portion of the Earth’s surface with just two or three satellites. However, these GEO satellites were large and costly, and the RF transmissions over such long distances resulted in significant latency.

The alternative, low earth orbit (LEO) satellites at altitudes of 60 to 2,000 km (99 to 1,200 mi), reduces signal propagation delay, but many more LEO satellites — several hundreds or thousands of satellites — are required to provide continuous coverage depending on the altitude. The velocity of LEO satellites, moving at around 17,000 miles per hour relative to a fixed point on the Earth, adds considerable complexity to maintaining data communications links.

Laser technology significantly enhances the functionality and economic viability of the various types of satellite systems, unlocking new possibilities and expanding the realm of what is feasible. GEO satellites can now provide high-speed, low-latency communications, and the radical improvements in SWAP of laser compared to RF systems make large constellations of LEO satellites more economically viable to build and launch.

Networking LEO and GEO
Optical communications also facilitate the networking between satellites at different altitudes to achieve efficiencies and optimize specialized tasks. For example, the U.S. National Defense Space Architecture (NDSA), which has since been renamed the Proliferated Warfighter Space Architecture (PWSA), is developing a network topology composed of two separate constellations: the Transport and Tracking layers, connected by optical links.
The Transport Layer is a resilient mesh network in LEO that allows information to flow quickly and securely around the globe and connects to ground stations. Mesh satellite networks provide resilience because data can be rerouted if one satellite is compromised or destroyed. The second constellation, the Tracking Layer, does remote sensing and observation, with infrared sensors to spot and track missile threats.

Another example of using laser links to network LEO and GEO satellites is the SpaceDataHighway (SDH), a public-private partnership between the European Space Agency and Airbus. The commercial service utilizes the European Data Relay System (EDRS) to provide high bandwidth capability to LEO satellites and airborne platforms by means of optical communications via the EDRS-A and EDRS-C geostationary satellites and ground stations in Europe.

Proliferated Commercial Satellite Constellations
Starlink, an ambitious project initiated by SpaceX, has made notable strides in its mission to provide high-speed internet to every corner of the globe. As of July 2023, 4,487 Starlink satellites are operating in low Earth orbit, with the newest versions of the satellites networked to each other with lasers. SpaceX anticipates the total number of satellites in the Starlink network to grow to between 12,000 and 42,000 eventually.

SpaceX founder Elon Musk tweeted last year, “Laser links in orbit can reduce long-distance latency by as much as 50%, due to higher speed of light in vacuum & shorter path than undersea fiber.”

The Starlink project is groundbreaking and transformative, but it is not without competition. One of the biggest competitors is OneWeb, a UK-based company that also aims to build a satellite network for global broadband service. Another formidable rival is Amazon’s Project Kuiper, which plans to deploy over 3,000 satellites for similar purposes.

Furthermore, China’s state-run space agency is also working on a global broadband service called Tianlink. Each of these competitors brings unique strategies and resources to the table, thereby contributing to an increasingly dynamic and competitive landscape in satellite-based internet services.

Aiming the Narrow Laser Beam
All these developments depend on the remarkable quality of laser light — the extraordinarily straight and narrow beam of light that can be focused on a distant target, transmitting data at incredible speeds and low latency, with minimal signal loss due to beam divergence.

And yet, it is the narrowness of the laser that makes it so difficult to acquire and maintain a line-of-sight link over distances of thousands of kilometers.

Aiming the transmitter and receiver is challenging due to the extreme precision required and because the system must quickly and smoothly adjust as the host satellites and spacecraft move at high velocity in different directions relative to each other and to ground stations. And the high-precision components must reliably stand up to the rigorous demands of space launches and the harsh space environment.

Fast steering mirrors require precision position data to rapidly adjust mirror position, which is usually actuated by electromagnetic voice coils. Extremely sensitive sensors can accurately measure the mirror position with extremely fine resolution in the sub-micron range.

The system is designed so that the performance of the sensors remains unaffected by the severe temperature fluctuations in the space environment. As shown in Figure 1, electronically matched sensors, using eddy current technology, are positioned in pairs on opposite sides of the pivot point of the mirror and equidistant from this point.

The sensor-to-target relationship is such that as the target moves away from one sensor, it simultaneously moves towards the other an equal amount. The two pairs of sensors are positioned in two axes set perpendicularly to provide precise x-y tilt/tip position data.  Operating in differential mode, the sensors eliminate or reduce common mode effects, such as piston action, and signal noise.  

Taking Aim at the Future
Kaman Precision Products, through its Measuring line of business, developed its line of differential position measuring systems over 30 years ago.  Kaman has continually refined the performance capabilities of these renowned products to meet the increasing requirements of the space and defense markets.  The product line now boasts three exceptional products including the KD-5100 family, with over 100krad TID capability and a rich 3-decades space heritage including the Mars 2020 Rover, as well as its COTS version, the DIT5200L, a low noise, affordable LEO-capable system, and our new digital KD-5690 system.  Learn more at (

Flycovr Offers Advice for Avoiding Risk in 2023

by Sam Kirtikar, CEO & Co-founder of Flycovr

Flycovr says when the odds don’t look great, don’t gamble and advises securing operational growth in 2023 by avoiding unnecessary risk.

The hurdle of the post pandemic global supply chain were heavily publicized, with four key areas consistently mentioned that could reduce frustrations. These were positive changes across procurement, logistics and operations; accurate data, better visibility across suppliers and the economic recovery of key industry areas.  

All very true, but with one very important omission in a post pandemic world and an unpredictable financial economy. The omission can be described in many forms whether financial exposure, risk management, contractual transparency or quite simply, vulnerable insurance gaps.

Businesses must take proactive steps to protect their commercial interests and avoid unnecessary risks. Not in case of another global crisis, but because of the everyday risks that are negatively affecting the bottom line across global supply chain operators.

Thousands of critical parts are required at short notice around the globe every week, and with e-commerce quickly increasing across the market, the risk exposure for critical cargo is only going to become more apparent. Flycovr’s partner, Loadsure, have stated that “over 60% of the U. S. freight market alone, is underinsured” and therefore at risk.

Whilst businesses seemingly spend so much time on the development side of operational growth, why is it that the risk of financial or reputational damage is so often ignored when it comes to insurance.

Flycovr says it has found three main factors that lead to underinsurance:

  • Lack of knowing or awareness of such risks
  • Complicated and laborious purchasing requirements 
  • The cost versus perceived benefit

This is all of course wrapped up in cynicism around insurers and their perceived lack of understanding around a complex aviation market, the company stresses.

However, aircraft parts in transit, are a common example of this area being misunderstood, when the liability of shipments is confused and the cover in place by the carrier is totally insufficient. Often, simple carrier insurance is done on weight and the usual policy holders are simply underinsuring, or certainly overpaying. Either way, the critical aspect, and aircraft part specifications, are not being considered fully.

Do you ever read your carrier policies? Traditional policies often exclude things such as acts of God or employee theft and across our supply chain, proving liability is a headache. Even when you can provide it, the claims process can be painful. “In some scenarios, we often see claims simply being ignored in fear of increased premiums” says Sam Kirtikar, founder of Flycovr.

As a matter of course, Flycovr encourages you to review your policies, and if you haven’t insured your shipments – ask why not. Especially when the market now has aviation specific solutions available to do this in one click.

Flycovr themselves offer access to lightning fast, all-risk, per-load smart coverage – brought to the aviation market specifically and available for instant access. Provided by Loadsure, this A.I. driven cargo cover is hands down the most innovative on the market and a solution to the global aviation supply chain underinsurance crisis.

Dalo Chouhan, CEO of Freight Source Logistics (FSL) now includes Flycovr in their proposition and offers digital cargo insurance as part of the offering to all FSL aviation customers to eradicate that risk and liability concern, “Our focus is on speed, security and efficiency of the supply chain, so offering global digital insurance cover on all shipments is an absolute value-added service to all FSL customers.”

Overall, each corner of the market plays a role in supporting a more sustainable supply chain and the aim is to create awareness where unknown risk exposures are rife.

Whilst the industry takes heed of these focus areas mentioned above and proactively enhances its operational delivery into 2023 – the message from us is to make sure this is all secured with the cost effective simple innovative aviation insurance solutions that will avoid all the financial investment and commercial growth being undone in one simple moment.

Dayton T. Brown Offers EMI/EMC Testing

EMI or EMC testing is essential for modern electronic devices to determine if the device can operate within its intended setting (environment) and in accordance with required standards.

Modern electronic devices must operate in today’s environments which are surrounded by multiple radio waves and electromagnetic (EM) energy. The device may even contribute to the amount of EM energy in the environment, in which case it is guilty of causing electromagnetic interference (EMI). For an electronic device or system to operate properly under such conditions, it must have electromagnetic compatibility (EMC) with its operating environment.

EMC is important for many electronic designs and especially critical for military, aerospace, and medical electronic applications, where lives may be at stake. Test standards have been developed over time to monitor and maintain acceptable EMI and EMC levels. Applying these EMI/EMC standards to a new or existing electronic product requires well-equipped test facilities and the engineering personnel with the expertise to evaluate the EM behavior of a device under test (DUT), unit under test (UUT), or equipment under test (EUT). Dayton T. Brown (DTB) has both the facilities and the engineering experience, offered in the form of complete EMI and EMC testing services to prepare modern electronic devices and equipment for problem-free operation in today’s EM environments.

What is EMI/EMC Testing?

EMI and EMC testing determines how EM energy can enter and escape from the EUT. EM energy propagates through the air, as radio waves, and travels through cables, wires, and other conductors, so that at least four different EM measurements are performed to determine different EM levels: conducted emissions (CE) and conducted susceptibility (CS) for cables and radiated emissions (RE) and radiated susceptibility (RS) for EM energy that may be escaping from or entering, respectively, the EUT over the air.

Guidelines for EMC Testing

Federal Communications Commission (FCC) Part 15 rules define the limits for unlicensed RFI that can be produced by consumer electronics and other devices. For military requirements, EMI and EMC measurements are usually performed according to the guidelines of MIL-STD-461 and MIL-STD-464, which outline EMC and environmental requirements for components/subsystems and systems for military applications. In the U.S. commercial market, EUT measurements are usually performed according to the guidelines of RTCA DO-160. International EMC and EMI measurements may refer to the International Electrotechnical Commission International CISPR (such as CISPR 22) and the International Electrotechnical Commission (IEC) standards, such as IEC 61000. Differences exist in the terminology among standards, with international standards referring to immunity rather than susceptibility as in U. S. standards.

Efficient EMI/EMC testing calls for high-performance test equipment and the people who know how to use it. It also requires effective test environments, well isolated from the world’s many sources of EM energy, from cell phones to radio towers. Shielding a test environment is not easy, especially as EM sources move higher in frequency, into the mmWave range with 5G wireless networks, collision-avoidance radars, and satcom systems. A shielded test environment must be large enough to accommodate an EUT yet provide the flexibility to rotate an EUT 360 degrees for full radiated emissions and susceptibility testing. DTB relies on more than 12 shielded facilities and more than 75 years of testing history to accommodate a broad spectrum of EUTs.

Who Should Care?

EMI is a problem that affects all users of electronic devices, not just the military. As the EM spectrum grows more congested with time, EMI and EMC testing becomes more important to ensure the “peaceful co-existence” of electronic devices within the operating environment. Excess EM energy levels can degrade the reliability of an electronic design, causing damage to susceptible integrated circuits (ICs) within its PCBs. EMI/EMC testing provides a way to foresee the behavior of an electronic design in controlled test environments and under conditions as close as possible to the actual operating environment.

The extensive knowledge and experience of DTB’s test engineers can simplify any preparations as part of the EMC pre-compliance or compliance processes. DTB can also ease EMC testing by explaining which EMC test standards apply to a particular EUT and which EM emissions and immunity tests apply to the EUT, such as standards from CISPR and IEC 61000 from the International Electrotechnical Commission (IEC).

Although causes for EMI are many and reasons for failing to achieve EMC may be even greater, DTB equips their experienced, knowledgeable test engineers with well-shielded anechoic chambers of various sizes and a full array of measurement instruments and tools under one roof for a wide array of EMI/EMC tests on EUTs for of all kinds for aerospace, automotive, commercial, medical, military, and space markets.

Who Can Help with Testing?

DTB shielded enclosures are large enough for complete system testing, even when the EUTs are contained within larger “containers,” such as vehicles. Test chambers are constructed with pyramid-shaped EM absorbent material to minimize unwanted EM levels (Fig. 1).

The DTB test chambers are well supported by the latest standard and custom test instruments for the generation and analysis of conducted and radiated EM emissions through 40 GHz. Test instruments include CW and pulse test signal sources to produce any combination of continuous, modulated, and random signals, standard and real-time spectrum analyzers with specialized accessories, such as EMI filters, for detection of custom signals, and EMI receivers capable of broadband frequency coverage. Aided by a wide range of test antennas and instrument-grade power amplifiers, DTB’s EMI/EMC test sets can generate EM radiated susceptibility fields more than 200 V/m.

Given the increasing consumption of bandwidth by modern electronic devices, EMI/EMC testing can be considered an automatic part of every new electronic product development. As the U. S. DoD seeks to take advantage of 5G cellular wireless networks and interconnected Internet of Things (IoT) sensors to improve logistics at military bases and depots, the importance of EMI/EMC for all involved electronic devices cannot be emphasized enough. Fortunately, DTB brings the experience, facilities, and tools to deliver the highest-quality EMI/EMC testing as needed for future supply-chain automation that will be reliable, safe, and secure.

HEATCON Composite Systems Announces Strategic Distributor Relationship with Watlow

HEATCON Composite Systems recently entered into an expanded distributor agreement with Watlow, a leading designer and manufacturer of industrial technology and thermal solutions, to provide standard products, services and thermal systems to the aerospace industry.

HEATCON Composite Systems is a leading global manufacturer and supplier of aerospace composite repair equipment and products with ISO9001, AS9100D and AS9120 certification.

For more than 40 years, HEATCON has supplied heating solutions to the aerospace industry—working closely with Aircraft Manufacturers (OEMs), Space and Defense Organizations, Commercial Airlines and Maintenance, Repair and Overhaul (MRO) facilities.

“We are excited about the new opportunities this partnership represents,” said Eric Casterline of HEATCON Composite Systems. “There is a large and untapped market utilizing Watlow’s products and HEATCON experience to reach those areas.”

Entering into this agreement with Watlow, HEATCON looks to expand the offering of thermal solutions to its customer base while supporting Watlow’s goal of expanding their presence into the aerospace industry.

“HEATCON is a respected and well-established partner of leading airframe manufacturers. Watlow is especially excited to work with HEATCON as we support this critical infrastructure sector with leading thermal products and industrial technology,” said Peter Gonzalez, Watlow’s director of global sales.

Watlow carries a variety of products that are ideal for HEATCON’s aerospace customers. These products include: temperature controllers, power switching devices, data loggers, electric heaters and temperature sensors.

Founded in 1922, Watlow has transformed itself into a diversified, industrial technology company providing thermal solutions to many of the world’s largest companies in industries such as semiconductor manufacturing, sustainable power generation, environmental technologies, medical equipment and aerospace manufacturing.

Jeff Guzzetti

NTSB Stresses the Importance of Aircraft Maintenance and SMS for Part 91 General Aviation Operators That Fly Paying Passengers

By Jeff Guzzetti

It’s about time.

The NTSB recently held two public Board Meetings to support the notion that preventing maintenance-related accidents is NOT just for the commercial airline industry that fly big jets under FAA’s stringent “Part 121” rules.  Sadly, several recent fatal accidents — all involving paying passengers — of small, propeller or rotor-driven general aviation (GA) aircraft have sullied the reputation of smaller commercial operations conducted under FAA “Part 91” rules. While the NTSB has a long history of concerns about these types of operations, the agency is no longer soft-peddling the issue.

During its meeting on March 26, the NTSB discussed and released their findings for a report entitled: Enhance Safety of Revenue Passenger-Carrying Operations Conducted Under 14 CFR Part 91. ( The largest portion of GA activity consists of pilots flying for their own personal or business purposes in single‑engine airplanes. Passengers on these types of Part 91 flights usually know the pilot, and expectations about safety are based on personal relationships.  However, a wide variety of other GA operations can provide flight services for paying passengers who likely have no knowledge of the level of safety afforded by the pilot or aircraft.

These accidents represent small and diverse segments of GA that transport the public for money, yet are governed only by Part 91 regulations. Why? Because their flight purposes are either exempt from the rules that apply to air carriers or are not covered by any other regulations. These Part 91 operations, which carry thousands of paying passengers each year, are not held to the same maintenance, airworthiness, and operational standards as air carrier, on-demand, and air tour operations conducted under Parts 121, 135, and 136, respectively.  That needs to change.

These “excepted” operations include local commercial air tour flights, sightseeing flights in hot air balloons, parachute jump flights, and “living history” flights conducted aboard historical military aircraft. In addition, some Part 91 commercial operators have exploited these exceptions by carrying people for money for purposes other than the exceptions intended, allowing them to avoid more stringent rules.

The safety issues of Part 91 revenue passenger-carrying operations cited by the NTSB were based on the findings from eight fatal accident investigations between 2010 and 2019, including two recently concluded investigations of accidents in Hawaii and Connecticut:

  • On June 21, 2019, a Beech King Ai,  operated as a Part 91 local parachute jump flight, stalled and crashed after takeoff from Dillingham Airfield in Hawaii. The pilot and 10 passengers were fatally injured. The NTSB determined that the probable cause of this accident was the pilot’s aggressive takeoff maneuver, which resulted in an accelerated stall.  However, they also stated that a significant contributor to the stall was: “the failure … to maintain the airplane in an airworthy condition and to detect and repair the airplane’s twisted left wing, which reduced the airplane’s stall margin.
  • On October 2, 2019, a Boeing B-17G bomber crashed during a precautionary landing at Bradley International Airport in Connecticut following an engine problem. Both pilots and five passengers were killed, while the crew chief and four passengers were seriously injured. The airplane was operated as a Part 91 local sightseeing flight.  The NTSB determined that the probable cause was the pilot’s failure to properly manage the airplane’s configuration and airspeed after he shut down the No. 4 engine following its partial loss of power during the initial climb. However, the board also stated that a contributing factor was the “inadequate maintenance while the airplane was on tour, which resulted in the partial loss of engine power to the Nos. 3 and 4 engines”

Everyone knows that airlines have an extensive safety infrastructure, are subject to stringent safety rules of Parts 121, and receive the highest levels of FAA oversight. However, flights operated under Part 91 are subject to much less stringent pilot training and aircraft maintenance requirements with minimal Federal oversight. The Board expressed the need for greater safety requirements and oversight for these operations, and they issued new recommendations to the FAA to:

  • Develop safety standards or regulations for revenue passenger-carrying operations that are currently conducted under Part 91 including requirements for maintenance.
  • Identify shortcomings in the current regulatory exceptions that would allow revenue passenger-carrying operators to avoid stricter regulations and oversight in operations.

Two weeks later, on April 6, the NTSB met again to finalize its 2021 – 2022 “Most Wanted List of Transportation Safety Improvements.” (  The Most Wanted List is a communication tool through which the NTSB identifies its top safety improvements that — if executed — will prevent accidents. The list covers all modes of transportation, but the primary item for aviation is “Require and Verify the Effectiveness of Safety Management Systems(SMS) in All Revenue Passenger Carrying Aviation Operations.”  

The King Air and B-17G accidents were cited again in the meeting because the NTSB determined that, besides the inadequate maintenance, organizational safety management failures played a role in those accidents. The NTSB stated that widespread adoption of SMS by Part 91 (and Part 135) operators could have a positive safety impact. They also encouraged Part 91 and 135 operators to voluntarily implement such SMS  — while simultaneously urging the FAA to require them – so that the safety of these operations can be improved. SMS was designed to be scalable so that operators could integrate safety management practices tailored to their specific operation.

I recognize that the public likely does not expect small, GA flight operations to have the same level of safety that airlines do; however, it is not unreasonable for the public to expect flights that are, at a minimum, conducted in appropriately maintained aircraft. It’s about time that these smaller operations to stop hiding behind the exceptions whenever they provide flights to the public for money. 

Looking for the Bright Side by Remembering History

By John Arcari

John Arcari

I suspect a number of you aviation maintenance industry folks might know that I spent just short of thirty years service working for Pan American World Airways, from 1958 to 1987. When I resigned from Pan Am, I went on to become the VP, Aircraft Maintenance for Tower Air, an American flag carrier serving international destinations and supporting military personnel movement operations, worldwide.
I hired on with Pan Am in 1958 as an aircraft cleaner to work through the busy summer time flying schedule, cleaning airplanes in the hangar at our JFK, NYC Airport, main aircraft maintenance base. At that time, Juan Terry Trippe, our chairman& CEO, was a aviation legend in his own time. When Labor Day came by in September, I was made a full time employee and in October, 1958, I was upgraded to full aircraft mechanic. And…so began my journey of many years with Pan Am that proved to be so educational and fruitful in my life!
Trippe was a dreamer, and in the early 1920s after serving in the Navy during WWI, Trippe began to get the urge to go into the airline business. He knew the finance business, but he just darned loved airplanes. He got some of his Navy buddies and college pals to dig up some cash to invest in a Trippe scheme to fly from Key West Florida to Havana, Cuba carrying American and Cuban mail and a passenger here and there. So, in October of 1927, in a leased Fairchild FC-2,  Pan Am became alive and a real operating airline. On October 29, 1927 a Pan Am owned Fokker V11 Tri Motor made the return flight to the USA.
Now at that time the roaring twenties were still roaring, but the storm clouds of a massive destructive depression was on the way, worldwide, quite similar to our depressed situation today, with such hardship and fear for millions of folks here in the USA and around the entire world. The health crisis has heavily impacted our beloved airline industry. 

However, none of those negative circumstances stopped or derailed the “Trippe Dream” of having a worldwide airline system. So, before  Charles “Lucky Lindy” Lindbergh  jumped off on his historic non-stop flight from Long Island, New York to Paris, France, Trippe made certain he stumbled into “Lindy” on Long Island. He convinced Lindbergh to join Pan Am after his historical, non-stop  jaunt across the sea! Lucky Lindy and his wife Anne, whom Lindbergh taught to fly, worked as a team flying through thick and thin. Charles and Anne did pioneer flight activity through the 1930s Great Depression across the world, including laying out safe routes to Alaska,  Siberia,  Japan and China. They also mapped route excursions in Latin, South America and the Caribbean. They to were both dreamers.

Then came the pilot of the century Captain Edwin Musick, an auto racer auto mechanic and the best Pilot in the world, in my opinion. Musick rose to become the chief pilot at Pan Am very quickly and flew and commanded many pioneer flights beginning in Florida/Cuba and extending around the world. Sadly the magnificent Musick was killed in a crash in the Pago Pago area of the South Pacific, near American Samoa. Musick was honored across the world. All of these capers were accomplished in the hardest of times in the USA and round the world, the 1930s era of the Great Depression. The world was in pain, but Trippe, Lindbergh, Music and many others like them in our beloved industry, stayed the course and birthed the airline industry that has changed this world a number of times, for the positive.

Just keep in mind my great band of aviation brothers and sisters in common…more positives were yet to come from the dreams and likes of Trippe and Lindbergh. the Boeing 314 Clipper, the Boeing Stratoliner, the Boeing 707 and the Boeing 747 might have never been developed, if not for the inputs of both Trippe & Lindbergh!

Folks in our industry and folks in many other industries are hurting at this time…but I believe the end is in sight and we will all come back stronger than before. The simple fact remains, this world of ours cannot truly reach its great destiny of positives without out airplanes bringing us together, whether it be for business, pleasure, travel, new ventures, movement of supplies and goods or visiting out own beloved families and friends.

We simply must band together, support each of us that makes up this magnificent airline puzzle, have faith in each other and our industry.We will be OK soon, just as Trippe, Lindbergh nd Musick were as the 1930s Depression came to an end. We shall return, stronger, better and more successful then we ever were! Have Faith, trust each other and trust in our Lord and trust in yourselves…and most important never stop dreaming. At eighty years young, I am not a naysayer, a doomsday fool and I have not stopped believing in our great destiny yet to come. I have not stopped trying, I never give up dreaming and I never will until my days have ended. We are coming back. big time…the world awaits!  I want to hear these words uttered and uttered over and over again.  “Captain, we have tower clearance for take-off…V1… rotate, landing gear up!”

Off we go – the glory of flight will soon return!

AAR Paves the Way to Improve MRO Safety with SMS

By Jeff Guzzetti

You may have seen the news clip last month in Aviation Maintenance announcing that the FAA now recognizes AAR’s Aviation Services as the first independent MRO to have a fully functional Safety Management System (SMS).  “AAR´s SMS implementation meets the expectations of the Flight Standards Service SMS Voluntary Program guidance,” the FAA stated. “Thank you for your continued commitment to improve aviation safety … and congratulations on your momentous achievement.”

Momentous indeed.  Airworthiness is a critical aspect of aviation safety. This noteworthy achievement should grab the attention of our industry because of the example it sets for other MROs to prevent aircraft accidents and injuries. AAR is the largest independent MRO operator in North America and the third largest in the world. The company employs over 3,000 technicians and provides maintenance for over 950 aircraft and 24,000 components every year.

The recent “Part 5” requirement to implement a SMS has only been levied on Part 121 major airline operations and maintenance. Other aviation entities such as MROs, Part 135 operators and training providers do not (yet) require SMS.  Still, AAR went ahead and volunteered to meet the mandate anyway by participating in FAA’s SMS Voluntary Program.

This is no easy task – especially for a large MRO and especially if you want to do it right. Don’t believe me? Spend some time poking around FAA’s internet page entitled “Voluntary Implementation of SMS which can be found here:

As a former FAA and NTSB investigator, I know first-hand that accidents occur due to the unique operating environment of an organization. SMS is a process in which day-to-day safety issues are discovered, analyzed and corrected internally by the organization, not its regulator. With its emphasis on risk management, SMS fills the gaps between “common cause” risk factors that are addressed by traditional regulations and those that are more elusive within an individual operation.

SMS is a fundamental shift in the way companies do business in that it emphasizes safety management in the same manner as business management. It may be too much to expect, but I believe everyone in aviation should be able to rattle off the four components of a SMS as if they were required memory items:

  • Safety Policy— Establishing senior management’s commitment to continually improve safety
  • Safety Risk Management — Identifying and assessing hazards in order to control their risks
    • Safety Assurance — Evaluating risk control strategies with audits and self-reporting
  • Safety Promotion— Training and communications to promote a positive safety culture

The first type of recognition into the FAA’s SMS Voluntary Program is as an “Active Participant” which is attained when the local FAA certificate management team (CMT) acknowledges the MRO’s “Implementation Plan” and the CMT’s “Validation Project Plan” for SMS. The second and final step is the SMS “Active Conformance” acknowledgement — achieved once both plans have been executed as intended and the SMS has been validated by the FAA for its design and performance.

In AAR’s case, the company’s Rockford, Miami and Oklahoma facilities began their SMS development process in late 2018. The Rockford facility received “Active Conformance” status while Miami and Oklahoma City are “Active Participants.” The fourth of AAR’s four U.S. facilities is in Indianapolis and it will soon be joining the other three within a few months.  Safety is journey, not a destination, and AAR gets it.

AAR’s achievement is all the more impressive given its circumstances several years ago when it under public scrutiny for not always emulating the best safety and compliance practices. You may remember the negative publicity about an Allegiant Airlines jet that nearly lost control on takeoff from Las Vegas in August 2015. The investigation revealed that the airline’s maintenance provider at that time – AAR — failed to insert a cotter pin on a critical flight control component and have another technician conduct a secondary inspection to ensure it was installed. Other repetitive maintenance issues were also discovered. AAR was on the cusp of being fined by the FAA and having its MRO certificate suspended.

Today is a different story. Kudos to AAR for committing to the arduous journey of voluntarily implementing a SMS. AAR is already reaping the benefits.  “Employees are excited about SMS because it provides an easy way to share their thoughts on how we can take our quality and safety practices to the next level,” a representative of AAR recently told me. “It helps to create a culture [where] people want to work every day.” 

Improving and promoting an organization’s safety culture is key because it is the “glue that binds” people together toward a goal that is larger than themselves. A quick glance at AAR’s annual reports and public records show that performance goals for safety have been established, its stated corporate value is “Quality First, Safety Always,” and FAA enforcement actions are nearly non-existent.

That said, I offer this unsolicited word of caution to AAR and any other MRO or organization that seeks an effective SMS program. In safety management, everyone has a role to play; however, the expectations that lead to a positive safety culture are created and maintained at the top of the organization. Leadership enables success only by its continuous adherence to what they profess, how they allocate resources, where they align their organizational goals and when they exude a strident unwillingness to compromise.  Without the continuous commitment of all levels of management, an effective safety program cannot exist.  SMS should not merely be a binder of slogans and processes that collects dust on a shelf. It must be fully integrated into the fabric of an MRO’s daily operations.

To conclude, I congratulate AAR for this achievement, and I am hopeful they will reach – and maintain — “active conformance” at its other MRO locations. Implementing the SMS framework is scalable with the size and complexity of any MOR or organization. AAR has paved the way. I look forward to seeing many other independent MROs follow their path to safety.





Bob Barron

Human Factors Training: How Do You Know It’s Working?

By Bob Baron, Ph.D

The Aviation Consulting Group

As your company’s Human Factors (HF) instructor, you have just finished conducting a two-day HF course for 20 aircraft mechanics. So, here’s a question for you: Was the training impactful enough to make a difference in on-the-job behaviors, and if so, is it possible to quantify the effects of the HF training?

Let’s start with the first part of the question. Unquestionably, the experience of the HF course itself can make a big difference in whether or not the mechanics absorb and transfer the classroom skills to the real world. A poorly developed, mundane course will likely bore the attendees and negatively impact the intended outcome of the training. This, combined with a disinterested instructor, who tells war stories for the entire course, or just reads the slides, pretty much guarantees that the training will be a waste of time for all concerned!

Now let’s shift to the second part of the question. With the assumption that the training course is well-developed and delivered, we want to know if we can observe and quantify the behavioral changes that have taken place as a result of the training. In other words, is there a positive transfer of knowledge, skills, and attitudes to the real world? To answer this question, we need to measure the performance objectives. Those objectives include, but are not limited to, building an awareness of errors and error-provoking conditions, and how the mechanic uses that awareness to minimize, or prevent, the commission of maintenance errors. To know if the HF skills, knowledge, and attitudes, as a result of the HF training, are having an effect, we can use the following methods:

Safety Performance Indicators (SPIs)

You already have, among others, the following SPIs-

  • Accidents
  • Incidents
  • Occurrences
  • On-the-job injuries

Use these indicators to look for trends on a year-over-year and/or month-over-month basis. If HF training is newly deployed, then theoretically there should be a downward trend in these indicators. If HF training has been an ongoing process, we hope to also see an ongoing downward trend. But trend is the key word. There will be safety events, even during downward trends. When safety events do occur, were they due to Human Factors? If so, you might need to further reinforce the transfer of training to the job. What went wrong? Why? How can we prevent it from happening again? Do we need to add/modify/expand on a particular HF topic in the training course (i.e., focus on particular problem areas such as fatigue, procedural deviations, assertiveness, communication, etc.)?

It should be noted that these SPIs can have both upward and downward trends, and that we are using correlations with the HF training. But, correlation does not mean causation, as there may be other intervening variables. However, with a strong correlation, we can be pretty confident in the results.



One of the most effective ways of determining whether there is behavioral change is by direct observation. Take a look around the hangar. Are the mechanics doing things the way they are supposed to be done? Or, are you noticing deviations from procedures (i.e., skipping functional checks, signing off inspections that were not completed, working on tasks from memory, etc.)?

It is important to point out that these types of observations are not meant to be punitive; but rather to identify systemic, human factors issues within the company. This can be done by surveying key people who observe the mechanics. Or, as the safety manager, you can just take a walk through the hangar at random times. You’d be surprised at how many things you will see walking from one end of the hangar to the other if you really pay attention.

Speaking of non-punitive observations, you might want to consider implementing a Line Operations Safety Audit (LOSA) for Maintenance Operations. A LOSA observation is conducted by a non-threatening company employee (typically another mechanic) who takes notes on what is happening during the course of normal maintenance activities. Once all the data are collected, then a report is written and recommendations are made to management to both reinforce the positives and improve the negatives.



Surveys can be deployed online and be anonymous and confidential. Surveys can provide a “peek” into the effectiveness of the HF training directly from the mechanics. A carefully constructed, short survey can measure attitudes, opinions, and beliefs about various aspects of the HF training.

While surveys are an excellent way of collecting a wealth of information, it should be kept in mind that surveys are subjective and any changes (if needed) to the HF training program should be based on an appropriate sample size. If your company employs 500 mechanics, and only 15 of the mechanics respond to a survey, the results will be questionable. The typical response rate for surveys is 20%-30%. Although this seems rather low, it should still be enough for statistical significance.



When it comes to interviews, trust is a must! With trust and openness, you will find that one-on-one, confidential interviews can provide an extremely useful source of information. Interviews should be done casually (avoid checklists and forms). Just listen and take notes. mechanics are generally willing to discuss things in a casual, personal interview that they may not want to bring up in other mediums. For instance, you might find a trend in mechanics not feeling comfortable submitting hazard reports in the voluntary reporting system because they feel it’s a waste of time and nothing will get done to fix the issues. You may also detect this trend in the survey responses discussed above. That’s why using a variety of methods to collect data is so important. There’s power in numbers!

Interviews can also be done in a focus group format. Just as with the one-on-one format, a focus group provides direct feedback from the mechanics. Focus groups can be more comfortable for the group attendees as they are discussing issues with other colleagues, rather than feeling singled out in a personal interview.

In either format, be sure to let the interviewees know that they have the right to refuse an interview and that there will be no repercussions if they choose not to be interviewed. Remember, this is all part of your non-punitive Just Culture.



For many companies, HF training is simply a “check the box” activity. These companies are not as concerned about the training’s efficacy (transfer to the job) as much as satisfying a regulatory requirement. That’s not what HF training is all about. You need to move away from the “check the box” approach and give your mechanics a reason to take what they’ve learned in the classroom and move it to the hangar. It starts with a well-developed HF course, with an effective and respected instructor/facilitator, and the appropriate, ongoing performance measures to ensure that the training is meeting its objectives.

On a final note, just because an HF class attendee scores 100% on the classroom written test, it does not guarantee the AMT will have the desired behavioral change on the job. Conversely, a mechanic that barely passes the written test may still have the desired behavioral change. This is one of the reasons why, in HF training, I put less emphasis on the results of written tests and more emphasis on the real test; the demonstrable transfer of knowledge to the AMTs on-the-job activities. This might include double checking work, not skipping steps, being assertive when needed, and much, much more.

Hopefully, this article has helped to answer the question of how do you know if your HF training is working. It’s a sad fact that many companies aren’t interested in reaching this level of detail regarding HF training effectiveness. But those companies that do, will undoubtedly be the ones that have a safer workforce, which in turn will show that HF training is an investment rather than an expense. The ROI will be quantifiable, and management will like that!


Dr. Bob Baron conducts aviation safety training, consulting, and program implementation for aviation operators on a global basis.

Sensitive and knowledgeable about various cultures, Dr. Baron uses his 32+ years of academic and practical experience to assist aviation organizations in their pursuit of safety and quality excellence. He has extensive experience working with developing nations and island countries. He also provides training and consulting to some of the largest airlines and aircraft manufacturers in the world, as well as civil aviation authorities and accident investigation bureaus.

If your aviation organization is interested in improving its culture, implementing programs such as Human Factors, SMS, or LOSA, or have an external, unbiased safety audit/Gap analysis, please get in touch.

Dr. Baron’s company, TACG, provides numerous training and consulting services. For more information, please go to