FEDEX Flt 80 MD-11 Crash

Re: FEDEX MD-11 Crash

News reports are saying no survivors. :( It's times like this I wish the reports were wrong like they sometimes are. RIP :(
 
Re: FEDEX MD-11 Crash

As Orange mentioned, striking similiarities.....at first glance... to the EWR accident.
 
Re: Planes crash...

<object height="285" width="340">


<embed src="http://www.youtube.com/v/i-OQKdmwOv4&hl=en&fs=1&border=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" height="285" width="340"></object>

Another website reporting both dead...

RIP Fellow Aviators
Wow, that actually looks really scary especially since I've never seen an airplane of that size porpoise before.
 
Re: FEDEX MD-11 Crash

Wow. The "media" had reports that one person was removed from the wreckage. Must have been one hell of a gust to lift it back up like that.

That's not a gust, that's the nose wheel.

It looks like he porpoised the thing down the runway ala a Cessna 182 when it's out of elevator. I've seen this happen a handful of times in GA planes, but never in a transport category jet.
 
Re: Planes crash...

Wow, that actually looks really scary especially since I've never seen an airplane of that size porpoise before.

Large plane like that, long spool up times for the engines...I wouldn't imagine that recovering from a porpoise is as simple as other planes where you can just power up, set landing attitude, and fly out of it.
 
Re: FEDEX MD-11 Crash

As Orange mentioned, striking similiarities.....at first glance... to the EWR accident.


serious question and only asking because I have no idea......

If I bounce in my 172 it doesn't take much to throttle up and get airborne.

How much time, etc... does it take for a major aircraft like that to spool up and get moving again? do they land with much power?
 
Re: FEDEX MD-11 Crash

serious question and only asking because I have no idea......

If I bounce in my 172 it doesn't take much to throttle up and get airborne.

How much time, etc... does it take for a major aircraft like that to spool up and get moving again? do they land with much power?

Wow...we just had the same idea at the same time...
 
Re: FEDEX MD-11 Crash

serious question and only asking because I have no idea......

If I bounce in my 172 it doesn't take much to throttle up and get airborne.

How much time, etc... does it take for a major aircraft like that to spool up and get moving again? do they land with much power?

Won't happen, I wouldn't think at least. Depending on how the thing is designed, the ground spoilers could already be up and trying to get you to stay on the ground. Once those things are up, as far as I'm concerned, you're staying on the ground. If you push the thrust levers up they'll come back down, but as MikeD noted, the spool up time would mean they've got a while before the power comes back up.
 
Re: Planes crash...

I wouldn't imagine that recovering from a porpoise is as simple as other planes where you can just power up, set landing attitude, and fly out of it.
I know, I was thinking the same when I watched that video...very sad and a scary sight. :(
 
Re: Planes crash...

Wow, that actually looks really scary especially since I've never seen an airplane of that size porpoise before.

+1.

That's an incredible amount of weight hitting the runway; I'm surprised it even held together after that second bounce.

That said, it's hard to imagine being on final approach to your own death, and not even knowing it.
 
Re: FEDEX MD-11 Crash

serious question and only asking because I have no idea......

If I bounce in my 172 it doesn't take much to throttle up and get airborne.

How much time, etc... does it take for a major aircraft like that to spool up and get moving again? do they land with much power?

Not speculating on the crew, since I wasn't in the jet, just some generalities.

I think the rule is 90% of rated thrust in 8 seconds during the approach phase. However, they were in the flare/landing phase from the video. If the thrust was at IDLE, it would take more. They are big motors with big inertia.

If you push the power up and only one of the outboards comes up on thrust, that could create a bad situation. (long sentence alert) IF, in that situation with the gusty winds, a crew would push the power up, and the wind gusted at the exact wrong time in the exact wrong direction, you could theoretically get a disturbance of the airflow around the nacelle, and creating a pocket of lower pressure air for one side of the engine, the air going through the compressor could exceed the critical angle of attack and create a compressor stall.

Is that going down the right path?
 
Re: FEDEX MD-11 Crash

I had the thought in my head, then read your post. I'm like a half-speed, half-as intelligent, maybe 1/5th skilled Orange Anchor.

The other one that pops is the MD-11 (or 10) that they ripped the gear off in MEM from a hard landing.

The --11 has a reportedly strong pitch-UP with spoiler deployment. This is mentioned in the NTSB pdf BUT the NTSB concludes the spoiler pitch-up tendency did NOT contribute to the EWR accident. ???

Surprised we don't have an -11 driver with experience to comment on the handling..not to speculate or comment on the crash but the -11's handling.

(FWIW.. not skill or intelligence but living long enough and reading too many accident/incident reports. Sad day for immediate family and those who knew this crew. )
 
Re: FEDEX MD-11 Crash

Fox had one of their "guru's" on saying the cargo version had a smaller horizontal,?? I could have this wrong.
 
Re: FEDEX MD-11 Crash

The --11 has a reportedly strong pitch-UP with spoiler deployment. This is mentioned in the NTSB pdf BUT the NTSB concludes the spoiler pitch-up tendency did NOT contribute to the EWR accident. ???

Surprised we don't have an -11 driver with experience to comment on the handling..not to speculate or comment on the crash but the -11's handling.

(FWIW.. not skill or intelligence but living long enough and reading too many accident/incident reports. Sad day for immediate family and those who knew this crew. )

I've heard the same thing from a buddy of mine that flies the MD-11. He said it's real touchy in the landing/flare phase.

I've never touched one, so I'll stop right there with that parrot from him.
 
Re: FEDEX MD-11 Crash

In looking at this, you'd think that the airplane could have landed straight ahead with damage; but what I want to know is what brought the wing up? Was it a control input or a gust that took the thing over? Or it stalled while bouncing and thus dropped a wing? That seems like more of a long shot idea.
 
Re: FEDEX MD-11 Crash

If you're at idle power and the spoilers with strong gusts are coming up I imagine Sir Isaac Newton is at the controls (ie. whichever spoiler comes up first, whichever engine spools up first, whichever way the aircraft gets weather vaned by the wind which induces whichever roll)
 
Re: FEDEX MD-11 Crash

Fox had one of their "guru's" on saying the cargo version had a smaller horizontal,?? I could have this wrong.

According to a number of sites, the -11 has a smaller horizontal than the -10 but that is NOT specific to the freighter version.

In doing some reading, China Air also had an -11 break-up on a hard landing at Hong Kong in 1999. CK 1642. Like the EWR, hard landing, gear collapses, wing separates, a/c goes inverted and crashes.

http://aviation-safety.net/database/record.php?id=19990822-0
 
Re: FEDEX MD-11 Crash

Good info on the history of the MD-11 and its flaws:
http://www.airlinesafety.com/faq/faq9.htm


The MD-11 was designed with a smaller horizontal stabilizer than other airliners. That, plus the shifting of its center of gravity further aft, all to reduce drag and thus fuel burn, causes it to be unusually light on the controls. That design, known as �relaxed stability,� is common to fighter planes but is not normally found in the pitch axis of a civilian airliner. It makes it more likely that the pilot will overcontrol and exacerbate the situation, during a recovery attempt after a high altitude upset or during a bounced/hard landing.

I have never flown an MD-11. However, I do have a description of its handling characteristics from a pilot that has had considerable experience in that cockpit:

The MD-11 is not fly-by-wire. It is, however, fly by CONSTANT pilot input. The geniuses at MD decided to make the empennage 40% smaller than the DC-10 to save on both parasitic drag and induced drag by keeping the c.g.[center of gravity] near the aft limit during high-speed cruise.

This airplane doesn't really have a "slot" when you are on final; it doesn't seem to really stay at a trimmed AOA [angle of attack] /deck angle at a specific power setting/airspeed. As such, the pilot is constantly making little corrections, like flying a dynamically unstable fly-by-wire fighter with the computer out. This is unlike any transport aircraft I've flown. Part of the problem is a system called the Longitudinal Stability Augmentation System (LSAS) which is a computer that constantly trims the stab to make up for the shortcomings of the tail size. The landing is also unique. As soon as the plane touches down I have to push on the yoke to counteract a severe pitchup from the spoilers coming to 2/3 extension. Less than a second later, the autobrakes kick in, so you have to pull back on the yoke to gently lower the nose to the runway.

Somebody once said they should let Lockheed design all the airplanes, Boeing build them...and McDonnell-Douglas market them! And let the French guys stick to making Citroens and Peugeots...

In my view, that unstable pitch mode constitutes defective design, which is directly responsible for all the deaths and injuries that have occurred during high altitude upsets and the resulting violent pitch oscillations.

I also think it reasonable conjecture that the Anchorage, Newark and Hong Kong landing accidents might not have happened at all if the MD-11 was designed with a stable pitch mode as are Boeing airliners. The kinds of conditions encountered in those accidents (heavy weights, short runway, wake turbulence, gusting crosswinds), are personally known to airline pilots of high experience. That is when the skills of the pilot are put to the ultimate test, and the design quality of the plane is revealed. It is precisely the time when the pilot, and all on board, need everything going for them.

The pilot must be skilled enough to instantly recognize what control inputs are needed, and the plane must be designed so as to respond instantly to those commands without excessive oscillations. The brain of the pilot and the brain of the design engineer must be simpatico. If they are not, then in my opinion, you get what happened in some of the accidents listed above.
 
Back
Top