What if McDonnell-Douglas DC-10 permanently grounded?

In 1979, when American Airlines Flight 191 crashed, this was a crash that grounded the McDonnell-Douglas DC-10 fleet for several months until new procedures for engine replacement and modified "stick shakers" were installed on the plane.

And interesting "what if" was if the FAA--who already had to deal with the defective cargo door issue that caused a THY Turkish Airlines DC-10 to crash outside Paris--decided there was too many technical issues with the DC-10 and ordered the permanent grounding of the plane (far out as it may seem in the OTL!).

In my humble opinion, I think this would have happened in the alternate timeline:

1. McDonnell-Douglas would have been forced to file for bankruptcy from the loss of the DC-10 program (the F-15 and F-18 programs wouldn't be enough to save the company), and there would be a bidding war between Boeing and Lockheed for McD assets. DC-9 production would likely end if Boeing snaps up the bankrupt McD, as Boeing will convert many outstanding DC-9 and MD-80 orders into 737-300/400/500 orders.

2. Lockheed would get a surge in sales of the L-1011, and Lockheed may pursue a twin-engined widebody airliner based on L-1011 components.

3. Boeing may experience a much larger initial order book for the 767-200 and 767-300 models as airlines scramble to replace widebody capacity lost due to the permanent grounding of the DC-10.

4. Airbus ends up selling more A300B's, and the A300B4-600 and 600R programs start earlier. American Airlines' original 34-plane A300B4-600R order could end up being doubled in size to 70 planes as the 600R's take the place of the phased-out DC-10's.
 
I know quite a bit about the AA191 crash, so this post may get a bit deep into the weeds technically.

This is really borderline ASB. The DC-10 was a widely used aircraft and an major component of the fleets of several major trunk carriers of the day including American, United, Continental and National. That an aircraft so widely used would be permanently grounded would have raised howls of protest from airlines that had millions invested in these planes and I find it inconceivable that the FAA would have taken such an action, particularly since the NTSB investigation of the crash revealed that the true cause of the accident was that American was cutting corners on how it swapped out engines, using a procedure that involved removing the engine and pylon as a unit that was not approved by the manufacturer and that was prone to creating fatigue cracks of the type that caused the crash.

Moreover, the hydraulic line/slat retraction and stickshaker issues that emerged as contributing factors were fairly easy fixes. Even the slat retraction wasn't by itself a fatal flaw; the plane would never have crashed had the pilots maintained a higher airspeed. The port wing stall was the result of a flawed engine loss procedure that called for a speed reduction. As a consequence, the port wing stalled and the aircraft became uncontrollable causing the crash. There was extensive post-accident simulator testing that proved this to be the case and the procedures were revised as a result.

The DC-10 went on to have a long and safe service life after AA191. So far as I can recall, it's only major fatal accident after that was the United 232 crash in Sioux City 10 years later that was caused by a catastrophic engine failure that resulted in a loss of all hydraulic systems.

Had the FAA permanently grounded the DC-10, it wouldn't have just been McDonnell Douglas facing bankruptcy. United and American might well have gone there as well. United, in particular, was in a vulnerable position as it was just emerging from a strike that had the line grounded for a couple of months. That two of the major airlines of the time plus a major and vital defense contractor would be forced into bankruptcy by grounding the DC-10 is something I think weighs heavily against a permanent grounding of the type. The pressure on the FAA to allow the DC-10 to keep flying would have been, to put it mildly, quite intense, especially since there was no genuine substantive reason to permanently ground the airplane.
 
The DC-10 went on to have a long and safe service life after AA191. So far as I can recall, it's only major fatal accident after that was the United 232 crash in Sioux City 10 years later that was caused by a catastrophic engine failure that resulted in a loss of all hydraulic systems.

And while that was exacerbated by certain aspects of the aircraft's design, the underlying cause was, again, a one-off error in manufacturing the No. 2 engine's fan disk, which neither McDonnell nor United had anything to do with, so it didn't really speak to the aircraft's underlying safety.

Really, permanent grounding is a very extreme step that would only be taken if there was overwhelming evidence that the design of an aircraft was unfixably flawed, which is almost certainly not going to be the case for any modern commercial aircraft; modern engineering practices are, of course, not perfect, but good enough to prevent truly unworkable designs from being used. Kit aircraft and the like may have their own issues, of course.
 
And while that was exacerbated by certain aspects of the aircraft's design, the underlying cause was, again, a one-off error in manufacturing the No. 2 engine's fan disk, which neither McDonnell nor United had anything to do with, so it didn't really speak to the aircraft's underlying safety.

Really, permanent grounding is a very extreme step that would only be taken if there was overwhelming evidence that the design of an aircraft was unfixably flawed, which is almost certainly not going to be the case for any modern commercial aircraft; modern engineering practices are, of course, not perfect, but good enough to prevent truly unworkable designs from being used. Kit aircraft and the like may have their own issues, of course.

The only permanent grounding I can think of is the Comet I; even the Lockheed Electra found its way back into the air once the vibration problem with it was identified and a fix devised. And that was a far more serious design flaw than anything involving the DC-10.
 
The only permanent grounding I can think of is the Comet I; even the Lockheed Electra found its way back into the air once the vibration problem with it was identified and a fix devised. And that was a far more serious design flaw than anything involving the DC-10.

And that goes back to the point, because the Comet's flaws had to do with a severe lack of knowledge about the pressure-cycling it was undergoing and metal fatigue at the time. They screwed up because they just didn't know they were making a mistake...not because they were incompetent.

About the only way I can see a permanent grounding happening in the modern world (meaning the '70s) is if someone writes control software which is then permanently (meaning baked into ROMs) installed on the aircraft and later found to have serious flaw(s). Even then, halfway competent engineering would let you pull circuit boards and replace the ROMs anyways once you had updated software.
 
I know quite a bit about the AA191 crash, so this post may get a bit deep into the weeds technically.

This is really borderline ASB. The DC-10 was a widely used aircraft and an major component of the fleets of several major trunk carriers of the day including American, United, Continental and National. That an aircraft so widely used would be permanently grounded would have raised howls of protest from airlines that had millions invested in these planes and I find it inconceivable that the FAA would have taken such an action, particularly since the NTSB investigation of the crash revealed that the true cause of the accident was that American was cutting corners on how it swapped out engines, using a procedure that involved removing the engine and pylon as a unit that was not approved by the manufacturer and that was prone to creating fatigue cracks of the type that caused the crash.

Moreover, the hydraulic line/slat retraction and stickshaker issues that emerged as contributing factors were fairly easy fixes. Even the slat retraction wasn't by itself a fatal flaw; the plane would never have crashed had the pilots maintained a higher airspeed. The port wing stall was the result of a flawed engine loss procedure that called for a speed reduction. As a consequence, the port wing stalled and the aircraft became uncontrollable causing the crash. There was extensive post-accident simulator testing that proved this to be the case and the procedures were revised as a result.

The DC-10 went on to have a long and safe service life after AA191. So far as I can recall, it's only major fatal accident after that was the United 232 crash in Sioux City 10 years later that was caused by a catastrophic engine failure that resulted in a loss of all hydraulic systems.

Had the FAA permanently grounded the DC-10, it wouldn't have just been McDonnell Douglas facing bankruptcy. United and American might well have gone there as well. United, in particular, was in a vulnerable position as it was just emerging from a strike that had the line grounded for a couple of months. That two of the major airlines of the time plus a major and vital defense contractor would be forced into bankruptcy by grounding the DC-10 is something I think weighs heavily against a permanent grounding of the type. The pressure on the FAA to allow the DC-10 to keep flying would have been, to put it mildly, quite intense, especially since there was no genuine substantive reason to permanently ground the airplane.

A very good summary.

The one thing no one else has mentioned is that deciding to ground the DC-10 would cause a MAJOR shortfall in military aerial refueling capability. The KC-10 was based on the DC-10 and would also be affected by such an act. The KC-135 fleet was in the midst of various service life upgrades at the time and could not have picked up the slack. Especially on long deployments KC-10s were the primary tankers due to their much greater capacity. Since they also had both a boom and a probe/drogue refueling capacity they were often used to refuel NATO and Navy aircraft when they were also tasked to refuel Air Force A/C.

I don't think even if Boeing bought McAir (like they eventually did) the DC-9/MD-80 line would have been shutdown. Airlines that have a major investment in the type would not have wanted to change and Boeing would not have wanted to take a chance on loosing the sales to those lines to Airbus (If you are making a major change like from DC-9 to B737 you might as well consider Airbus as well) Boeing rebranded that later model of the DC-9 as the Boeing 717 (Reusing the model number that had been assigned to the KC-135 airframe) and kept it around for almost 10 years

Although the idea of Lockheed buying McAir is enticing they were involved in the bribery scandals at the time so would be working at a disadvantage.
 
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I think if my "what if" permanent grounding scenario of the DC-10 had happened, it would have affected American Airlines more than United Air Lines. Here's the reason: United could have pulled a number of DC-8's they had started to retire out of the "boneyard" and put them back into service as a stop-gap measure until the 767-200 started in enter service in 1982. Unfortunately, a permanent grounding would have seriously affected American Airlines until the 767-200's ordered arrived from November 1982 on.
 
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