A 1989 thought on fuel efficiency from McDonnell Douglas

Trolling the Flight Archive today, I came across a truly eye-opening gem of a quote from a June 24, 1989 article on McDonnell Douglas’ selection of a final assembly site for the MD-90. In the article, then program manager Walt Orlowski discussed the company’s decision to not offer the “technically ready” General Electric GE36 unducted fan for the re-engined jetliner, which was available for a $1 million price premium.  He described the company’s thinking this way:

Douglas concedes that, with fuel prices unlikely to rise substantially in the near future, there is “inadequate motivation” for airlines to gamble on unducted-fan technology in return for improved fuel efficiency.

Hard to tell what might have played out for McDonnell Douglas if its thinking had not been as short-term, especially in light of the fuel crisis that hit only decade earlier.

7 Responses to A 1989 thought on fuel efficiency from McDonnell Douglas

  1. Speed August 31, 2011 at 2:25 pm #

    A quick look at oil prices from 1987 to present shows that there was little increase from 1989 levels until 2004, aside from a brief bump in 1990.

  2. Aero_Ag August 31, 2011 at 2:29 pm #

    For the next 10-15 years, they weren’t far off. Even when Boeing was pitching the Sonic Cruiser in the early-00s, labor was a bigger cost than fuel.

  3. alloycowboy August 31, 2011 at 2:54 pm #

    Hey Jon,

    I wouldn’t bet on seeing unducted fans on any aircraft in the future ethier as ducted fans have had years of optimization to improve their efficiency. So while ultimately in the long run unducted fans might be the most efficient engines they are always behind in the horse the race.

  4. Guru Josh August 31, 2011 at 3:15 pm #

    The GE36 was never close to “technically ready” beyond TRL6, neither was any other unducted fan, ever. Vibration-hardened 30,000shp gearboxes and 8-10 blade propeller pitch change mechanisms alone may pose insurmountable mechanical problems.

  5. StarBlue August 31, 2011 at 3:21 pm #

    But the one problem with a UDF is the NOISE! It was one of the issues that both Boeing and Airbus could not quite overcome. I think the last one I saw was an Airbus rendering where the engines would be nearly impossible to get to on the ramp.

    I won’t say never, but with geared turbo fans starting to take hold I am not sure a UDF will ever been on anything but a military application.


  6. AirShowFan August 31, 2011 at 4:34 pm #

    For everyone who thinks that unducted fans will never be seen on a production transport airplane, I invite you to look up the Antonov 70. You’re not wrong – it’s still in the prototype stage and might not make it into production – but it was built with the intention of getting it into service, not just to test the idea. That having been said, unducted propfans are probably too noisy for most airports, and THAT is probably why (as far as I can tell) we won’t be seeing unducted propfan airliners anytime soon.

  7. John in CA September 1, 2011 at 12:56 pm #

    I was working at MD during the flight trials of the UDF. Hate to say it…but lot of misinformation up above….

    The MD80 test bird was actually a production plane that almost broke in half during a max decent/landing test…pretty neat video to watch as the tail falls off….you can see the fuselage buckle in the middle. I think the plane is still out at Edwards…

    Noise? No…it was quiter than other high bypass turbofans of the time. About the only noise issue was inside the cabin back by the blades…but that was not a real big issue.

    It was neat to watch it take off from Long Beach….interesting sound…

    The biggest issue was concerns of safety on the ramp and having to retrain mechanics to work on them. Most airlines have a specific skill set for their mechanics to match the planes they fly….the UDF’s fuel savings were no enough to justify the additional A&P’s to work on them. Now, if the UDF becomes mainstream? Different story.