BeagleFlyer - Did you (hopefully) let them know as you were deplaning, so that it did not depart for another flight in that condition?


What's not known is, whether that latch was open prior to departure, or "popped" after leaving the gate. (no rearview mirrors on a 737 :p ) Yes, this might be difficult to see on a walk around. However, it may not have been in that state when they left the gate. Those latches are usually pretty good. It takes a "double click" (not like a computer mouse) to open/close them. Some of the taxiways the country are pretty rough. If the acft was taxiing at a good rate, on a bumpy taxiway....and it was not FULLY latched to start with, it may have popped open. Not likely certainly, but at least feasible/possible.
As another poster indicated.... ^ for redundancy.

I had my instructor simulate an engine failure (777) after V1 and before takeoff at one of the DOs. The plane gets off the ground by the end of the runway (as it should). The only difference is that it handles 'sluggishy' when turning as you would expect and turns more slowly since the computer has already used a lot of the rudder deflection authority to keep the plane straight when it sensed the malfunction. I would expect 100% of commercial pilots to handle this problem and get the plane back safely.

Yeah, it's not the engine failing that's the problem. It's the damage debris falling off the engine and smacking the plane causes.

Look at AA 191, it wasn't the engine falling off the plane that caused the crash. It was the engine beating the wing to pieces and destroying the hydraulics as it went by...

The previous poster assumed the engine would fall off. If that happened during take-off, I'm not sure the outcome would be nearly as clean as your scenario assumes.

I know this was a long time ago, but let's not forget the one time an engine actually fell off was the horrific accident of AA 191.

As others have written, the problem wasn't so much the lack of power or balance, but that the engine that fell sliced through much of the hydraulics making the a/c impossible to control:

http://en.wikipedia.org/wiki/America...nes_Flight_191

...And since that time a l:)t has been done to reroute hydraulic lines, change the way engines break away, etc.

Hmmm, not sure that if an engine that fell off and sliced through the wing (as it did on AA 191), that the newer technology would actually avert a catastrophe.

Remember, in the AA 191 incident, the engine fell off, and because of intake fan rotating at high speed, a "helicopter effect" was created, it flew above the wing and sliced right through the entire wing.

No technology can ever change those basic physics...

There was recently an incident of an engine falling off (or more accurately being released by a safety mechanism) in Africa. In that case, there was no damage, and the plance landed safely (it was a 737).

Here is a link to the story:
http://articles.cnn.com/2007-11-08/w...el?_s=PM:WORLD

I think a more analogous incident to what might have happened in this case, was the QF A-380 incident, when an engine failure in the engine sheared a panel off the engine nacelle. In that case, there actually was quite severe hydraulic damage, but the pilots were able to land safely.

Had that same incident occurred on take-off, it's not as clear what the outcome might have been.

But if the liberated cowl damages the slats and the pilot doesn't know it, you may end up with asymmetric slat deployment and that has ended poorly in the past.

Both maintenance procedures and future designs were changed as a result :)f this incident. Wikipedia says this:

Absolutely.

Again, I'm not so sure that the design changes are really the key, but they have certainly made modern a/c safer than the DC-10.

But the real cause of this incident was AA's maintenance procedure which did not follow McDonnell Douglas's guidelines, in order to save time.

As a result, the engine was not properly attached to the nacelle, and that was the primary cause for the accident.

But if a catastrophic incident of this type were to occur on take-off, there is very little safety margin before the a/c reaches its stall speed. With one engine down and possible damage to the airframe and hydraulics, this would be a very tough situation to master, even in a modern a/c and with an experienced pilot.

If the crew of AA191 had known that the slats on the left wing had retracted then they could've selected flaps up/slats retracted. While the climb would be sluggish, the NTSB determined that they would've been able to return to ORD. The problem with the DC-10 was a design fault that a complete loss of the hydraulic pressure on one wing could happen w/o affecting the other wing and that there was no cockpit indication of such an abnormal configuration. The crew handled the emergency exactly per the info presented to them, that #1 engine had failed. A roll to the left would be expected. They were not expecting the extreme roll caused by slats up on the left wing and down on the right. The official cause of the accident was an "asymmetrical lift condition". The loss of the engine was only a "contributing factor".

An AA 727-200 lost an engine ("lost" is a common term for an engine failure) enroute from DFW to SAN in April 1985. The mechanic meeting the flight on arrival was dumbstruck as to what he found. He reported to the crew they had lost #3. The crew replied, yea, without warning they lost #3. The mechanic had to repeat, no, you lost #3, it isn't attached to the plane. The engine was never found.

Engine mounts are actually designed to have a breakaway threshold. If an engine were to shed a few fan blades, yet remain running until the crew reacts, the resulting out-of-balance at 50,000RPM could shake the wing to pieces. The preference is to have the engine fall off.

DL had a 737-200 engine breakaway on takeoff from DFW (1990's ??) Flight returned for landing. The engine separated from the wing, but remained on the aircraft with some cables designed for such (on the -200, the engines are mounted on/underneath the wing, not on a pylon forward/lower of the wing as on newer models). I don't remember, but think the engine mounts broke at their breakaway point even though the engine wasn't (otherwise/prior to the break) in trouble.

Back to the OP, having the cowling come off is not too serious. The higher concern would be the damage it might cause as it rips away and then possibly strikes other parts of the plane.
http://img215.imageshack.us/img215/7900/hpengine.png

That's clearly all right. The issue, though, is that when all this happens on take-off (the AA 191 engine started falling off before the plane left the ground), there is very little time or safety margin to deal with, a heavy plane not flying much faster than its stall speed, although the design flaws unique to the DC-10 would no longer be an issue. The AA 191 remained airborne for only a few seconds.

The issue is indeed the damage caused by the engine ripping away, and it is hard to predict what would happen in another take-off incident.

See what happens when you run out of duct tape?

Slightly OT, but as AA 191 was mentioned, it reminds me of one of my favorite stories about my wife.

A few years ago she was flying MCO-ORD and realized that coincidentally, it was May 25th and the flight number was 191 (United). This was a very eerie coincidence for her. When she was a very young girl, her family was going to Los Angeles for a wedding on May 24, 1979 on AA 191. However, they had to drive to ORD from their home in SBN and ended up missing their flight, so AA rebooked them for the same flight the next day. The next day, she and her family would have been on AA 191, however by chance they showed up at the airport early and the airline put them on the next earlier flight. Being long before the cell phone age, they were all safely en route to LAX when 191 went down, and everyone in LA had no idea they had gotten on an earlier flight.

Another eerie coincidence is that the infamous DL crash of an L1011 in DFW due to a thunderstorm downdraft was also flight #191. Perhaps that number should have been retired.

There was a hydraulics leak in that one as well. The Sioux City United crash in the early 90s had a similar outcome.

If there was a clean break, well, see above.

Silly misunderstandings aside, that's actually a very good password.