Thanks to the combination of an increased demand for new passenger aircraft and the global explosion of online shopping; passenger-to-freighter conversions are bringing new life to aging airframes.
What does English inventor Michael Aldrich have to do with the rapid growth of passenger-to-freighter (P2F) conversions? Well, probably a lot more than you think. Aldrich invented the Teleputer, which was the fusion of a PC, a TV and early telecom networking technologies. This invention, along with his other work in broadband communications, led to his introduction of the technology that enabled reliable online transaction processing between businesses and consumers, i.e., online shopping or e-commerce.
But, how does that relate to P2F conversions? Simple: with the need to move millions of packages on-demand, e-commerce giants like Alibaba.com and Amazon.com wouldn’t exist without overnight airfreight. Consumers want what they bought online today delivered tomorrow.
Overnight airfreight is so important to their business model, that Amazon.com recently signed a deal to lease 40 converted 767’s. There are also strong rumblings that the e-commerce giant is talking to Boeing about buying factory-new 767 freighters, but no official word yet.
And from the looks of it, that’s just the tip of the proverbial iceberg. According to Ed Clark, vice president of Commercial Managed Programs, Boeing Global Services, “Per the current market forecast, 2,480 freighters are required to meet the market demand over the next 20-years (920 new and 1,560 conversions).”
“Currently all standard-body freighters in the market today are converted airplanes,” he said. “Boeing forecasts market demand for 1,100 standard-body converted freighters and more than 460 wide-body converted freighters. We expect demand for the medium wide-body airplanes to continue strengthening, driven primarily by e-commerce.”
“In my opinion, the narrow- (standard) body segment there are the 737-300/-400 and the 757-200 and we can see the entry of the 737NG (-700/-800) in the near future,” explained Jacob Netz, senior consultant with Air Cargo Management Group. “Within the segment of the midsize wide-body freighters is the coveted 767-300. At Airbus, some of the last A300-600s are still in conversion, but the future lies with the A330-200/-300 conversions.”
“As for the large wide-body freighters, that conversion market is stagnant now,” he said. “Some believe that increasing demand for the retired 747-400 will pull some retired freighters back into service, but that seems unlikely now. Right now, the future belongs to the new 747-8F and the 777F. Both of which are new aircraft so there are no conversion projects underway.”
Of course not all of the freighter fleet additions will contribute to fleet growth. According to the Boeing Current Market Outlook 2017 – 2036, of the 2,480 freighters added to the fleet, 53-percent will be to replace retiring aircraft and the others will help meet projected cargo traffic growth around the world.
The Wide Lead for Narrow-Body Aircraft
Boeing’s freighter forecast also states that about 70-percent of the anticipated P2F conversions will be in the standard/narrow-body category, which is led by the Boeing 737-series freighters.
“It’s (737-300/-400) the standard for the narrow-body freighters at the moment. Everybody loves them,” stated Robert Convey, VP Sales and Marketing for Aeronautical Engineers, Inc. “Their economics make them ideal to serve the freight integrators’ – Amazon, Alibaba, DHL, UPS – primary need to move freight from satellite airport to the main hubs.”
“In particular, the -400 holds a standard size container like its predecessor, the 727, so there’s good commonality there for operators,” he said. “The problem with the –400 is we are running out of good, affordable feedstock. We just delivered our one-hundredth 737-400 and when we are finished we will have done about 150 total.”
“While the classic 737-300/-400 airplanes will remain viable for conversions for two- or three-more years, the need for more advanced avionics, better fuel efficiency and lower operating costs will increase,” Clark said. “The Boeing 737-800BCF (Boeing Converted Freighter) is well positioned as a next-generation freighter.”
“We’ll be transitioning over to newer NG-series 737’s, (-800) so you’ll see 20- to 25-year old airplanes being converted that will then fly fright well into 2050s and beyond,” Convey said. “Boeing is going to make around 4,000 NGs. That availability, along with good market acceptance and pricing, are the factors that make it the perfect going-forward narrow-body conversion platform.”
A Good Conversion Starts with the Right Airplane
So how do the major freighter conversion providers decide on which aircraft to covert?
“It’s a little bit of black magic to figure it out,” Convey said. “You need large numbers and good pricing obviously, but you also need aircraft that are constructed of a method that is rugged enough for freighter operations.”
“Boeing typically makes very robust airplanes, which are perfect. (McDonnell) Douglas certainly did, but their airplanes were very heavy. The current Airbus narrow-body fleet are very light and agile – perfect for passenger use, but not very good for freighter conversions in my opinion,” he said. “You also have to look at the configurations of the wings and engines.”
“For example, the Airbus A320 configuration is not good for installing a large cargo door ahead of the wing,” Convey said. “It’s got some critical components right where the left-side door needs to go and we can’t change that. Airbus can, but as a non-OEM, it’s game over on the A320 conversion for us.”
“Aft of the wing on any airplane you have the stress affects of single-engine out torsion on the empennage – excess torque on the tail. The door made the area too weak to those stresses,” he said. “Another issue with doors behind the wing is the sweep of the wing. The A320 and MD80’s wings are too swept to safely maneuver loading equipment in that aft area.”
Once you have the right model, the next determining factor for aircraft selection is an airframe’s age. But in the world of conversions, age isn’t measured in years: it’s measured in cycles. And, as you can well imagine, the lower the cycles, the higher the aircraft’s cost.
That fact is forcing operators to now consider airframes that were destined for the recycling bin just a few years ago. In fact, in today’s conversion market, even a nearly 30-year old airframe is attractive if the cycle times are low enough.
“Today, operators will by that airplane and spend $1.5 million on a conversion and another $1.5 million on maintenance and then put it back on the road for another 10-years,” Convey said. “It’s not an ideal situation, but in many cases it’s the best you can do now.”
He said that today’s freight expediters are also more open to converting aircraft with higher cycle times than they were in the past. For example, at 50,000 cycles there are extensive non-destructive testing requirements on a Boeing 737-400. But, as expensive as these inspections are, buying a higher-cycle -400 and doing the all the maintenance is still less expensive than a newer -800 right now.
“You have to keep in mind that the typical short-haul freighter utilization is not very high compared to airline standards,” Convey said. “It’s typically a thousand hours a year and it’s a one-to-one cycle. Most operators fly them two or three flights a day, five days a week. So they’re not putting huge numbers on the airframes.”
No Two Conversions are the Same
No matter the aircraft type or age, the “typical” P2F conversions share common steps including a thorough airframe inspection, removal of all the passenger equipment (seats, galleys, lavatories, stowage bins, oxygen systems, etc), removing or deactivating passenger doors, replacing and/or reinforcing floor beams, installing the main deck cabin door (MDCD) and its operating system and the 9g rigid barrier/net, and whatever else is required.
And while that all seems pretty straightforward, don’t for the moment think that these are “cookie-cutter” projects.
“When an aircraft is grounded for conversion there are aircraft owners that take advantage to perform fleet standardization or upgrading of the avionics or other systems,” Netz explained. “In addition, this downtime is also an opportunity for perform AD’s and SB’s like the lap joint AD on the 737-300 series.”
“With the typical 737 conversion taking three-months, performing these kinds of tasks as well as C- or D-checks while converting the aircraft will generate significant saving and minimize overall downtime for the operator,” he added.
“The term ‘standard’ is not appropriate for conversions,” Netz explained. “Each aircraft is an individual challenge for the conversion designers. For example, each aircraft has its own history. Aircraft arriving from different production series and many have undergone different maintenance or major repairs.”
“While the newer NG-series will probably be more standardized, the 737-300/-400’s were not computer-built airplanes,” Convey said. “There aren’t huge differences, but for example, some have chemically-milled skins and some don’t. We also find differences in frame and fastener locations.”
“We get into a conversion and suddenly find a fastener landing in the middle of nowhere, so we have to go get an engineering order (EO) for the deviation for that installation,” he said. “There are probably a dozen deviations for every conversion we do now. It’s no big deal. Our original conversion STC was based on an older airplane and they change over the years.”
“Obviously we don’t know about the changes until we encounter them during a conversion,” Convey said. “Our engineering team just has to be flexible and work with the airplane we have. It can be an interesting challenge.”
Conversion Magic: Turning One Bombardier Q400MR into Five
While successfully completing a P2F conversion would be enough for most companies, Bombardier-series conversion experts Flying Colours Corp., recently won a contract from Conair to convert six off-the-shelf Bombardier Q400MR turboprops into aircraft capable of handling any of five different mission profiles and combinations thereof.
“We will receive the brand new Q400MR aircraft at our St. Louis facility where we will handle all of the engineering, fabrication and installation of the various interior options and accessories,” explained Sean Gillespie, EVP, Flying Colours Corp. “There will be a commuter configuration with up to 64 seats, a cargo configuration, a combi-transport configuration and a medevac format for up to six patients. And of course, there’s the firefighting version with Conair’s proprietary retardant delivery system which can carry water or fire retardant.”
“The engineering to be able to develop solutions that can be quickly changed in the field is quite a challenge,” he said. “Especially when you consider that while the Q400MR has a long fuselage – perfect for this type of work – it’s not a wide fuselage. So space is a premium.”
Gillespie also said that one of the biggest hurdles has been designing and producing the flexible interior shell kit for the sidewalls, headliner and windows.
“Some of it will stay in the airplane in various configurations and some will not,” he said. “In addition, you have to take into account all the various safety regulations for each configuration, especially when changing from commuter to cargo or a combi configuration.”
“Another challenge for our engineering team is to make as many of the components common to as many of the configurations as possible to minimize transition time,” he said. “Probably the biggest challenge for that is the combination medevac and passenger configuration. It will have up to six ICU stations on one side and passenger seats along the other side.”
“If you take the firefighting side away, we’ve done all these types of conversions before, but this is the first time we’ve done them all on one aircraft at one time,” Gillespie said. “It’s a very unique project and we are delighted to have been awarded the contract.”
Gillespie said that by the time you’re reading this the first Q400MR is well on its path to becoming the first five-role player in the Conair fleet. Once that aircraft is completed by Flying Colours it will be returned to Conair to have all of the retardant delivery equipment installed at their facility.