Sr111 Landing

[rokky]

There are some situations that a pilot just can't win and SR111 was one of them.
Even if they would've made it to YHZ, they would've crashed on impact due to the MD11's flawed handling on landing because the LANDING GEAR is a focal point of concern on this aircraft.

The landing gear can't withstand any amounts of Negative G such as might be encountered by "pushing the nose over" in an attempt to unload the wings and that most - if not all landings - have to be made with the main landing gear all contacting the landing surface at one time.

SR111 landing would likely have required more runway than the 8800 FT available on RWY 06 at YHZ.

Given that, they should have taken the aircraft to another airfield - an airfield that would've been more than 13 minutes away.

Every heavy driver knows that there is a fine line between being quick and too quick in putting a malfunctioning jet on the ground.

The goal is to get the aircraft safely stopped on the ground in as short a time as possible, not to go missed approach or off the end of the runway in as short a time as possible - those same heavy drivers know that you get no bonus points for being so fast you can't land on the short runway.

[Kip Powick]

Re Swiss Air.............I would have rather taken a chance in going off the end of the runway sans gear rather than turning into a flaming lawn dart and ending up in Davy Jone's Locker.

There is one cardinal rule that 'most' drivers, heavy or not, follow..............evidence of fire....................GET IT ON THE GROUND.........breaking the aircraft and having some survivors, in my opinion, is better than worrying about max landing weight and what officialdom will do to your career......... should you break the aluminum tube !

IMO............ there is no fine line between being quick ....and too quick to get an aircraft on the ground when confronted with irrefutable proof that you have a fire onboard.

Nation Air was, unfortunately, another example of not being " too quick" and I would think all pilots would have taken a lesson from that terrible accident.

[Mitch Cronin]

Sorry Rokky, I'm thinking you might be out of your tree with regard to the MD11's gear..... Is it any different than a DC10's gear? I thought they'd kept everything pretty much the same?

[Don Hudson]

The TSB Report stated that the aircraft could not have made the runway before control was lost, (IIRC, LOC was only 23 minutes after the initial discovery of smoke).

It reminds me of the one sim exercise many of us did on the captain's upgrade - it was the last ride before going for line indoc training and they threw the kitchen sink and all the washing that needed doing at us. The goal was "get the airplane on the ground", period, with whatever the sim instructor left you with...

I think in this case, we have a cultural as much as an operational issue. "Measured/methodical" was the approach at Swiss, and for proven, good reasons. The other end is sometimes sported by our American friends when making it up and flying the machine to the ground, casting everything out the window in terms of SOPs, (they're a guide, after all). Both are good tools in the kit.

I've often wondered what I'd do when confronted with fuselage fire of unknown source on board over the Atlantic or Pacific. The decision went generally one way; - people were going to get wet and cold, very shortly. It wouldn't be pretty as we would expect. Using best efforts, you can get a transport airplane down from 6 to 8 miles up in about 10 minutes depending on type. The A340 would do about 6000fpm without overspeeding, until you got into thicker air. That's probably typical these days. The DC8's engines could be placed in reverse in flight - the quickest was the DC8-43 with a limit of MCT on all four while in reverse, in flight. The descent rate was about 16,000fpm. The later series were limited in reverse-in-flight to the inboards. Practically speaking I figure the exercise would take about 15 minutes all in, from initiation of the descent, a couple of miles to slow down, and "touchdown". That's not enough to get everyone ready, but it's enough to get most of them ready. The challenge of course is darkness and height/direction of the swell.

I don't know of any recommendations to depressurize the airplane sufficiently to starve the fire of oxygen. The O₂ on board was designed to last just long enough to do the expected descent profile. Descent to something like FL250 where many people could survive if in good shape is a possibility but the thinking is, if there's sufficient oxygen to keep most alive after the bottles run out, there's sufficient for a fire.

In truth, there's no book for this scenario, (but pilotless airliners are 'just around the corner').

AFAIK, Kapton is still standard-use in aircraft manufacturing. That's not the initiating problem though - the insulation just caught fire easily. It was the entertainment system that was shorting, wasn't it?

[Mizar]

There are some situations that a pilot just can't win and SR111 was one of them.

Even if they would've made it to YHZ, they would've crashed on impact due to the MD11's flawed handling on landing because the LANDING GEAR is a focal point of concern on this aircraft.

The landing gear can't withstand any amounts of Negative G such as might be encountered by "pushing the nose over" in an attempt to unload the wings and that most - if not all landings - have to be made with the main landing gear all contacting the landing surface at one time.

SR111 landing would likely have required more runway than the 8800 FT available on RWY 06 at YHZ.

Given that, they should have taken the aircraft to another airfield - an airfield that would've been more than 13 minutes away.

Every heavy driver knows that there is a fine line between being quick and too quick in putting a malfunctioning jet on the ground.

The goal is to get the aircraft safely stopped on the ground in as short a time as possible, not to go missed approach or off the end of the runway in as short a time as possible - those same heavy drivers know that you get no bonus points for being so fast you can't land on the short runway.

http://aviation-safety.net/database/record.php?id=19731103-1

Here is an example of a crew that delayed due to fire and paid the price.

I believe the AC DC-9 also delayed an emergency descent and look what happened.

The guys below survived after landing immediately. Full speedbrake and max speed.

http://aviation-safety.net/database/record.php?id=19960905-1

Remember, you can always dump while on descent for an immediate landing and if you are heading for one that is too short, then you can decide to go-around on final if the situation turns out to be not so bad.

I have never heard anything about negative g limits on landing gear. And usually you don't push a lot during the landing phase.

Descending fast doesn't mean you have to land fast.

[boestar]

I am still trying to figure out what Negative G on a landing gear is..... When extended in flight the weight of the gear is supported by the aircraft. when on the ground the weight of the aircraft is supported by the gear. The only way for that to change is to supply extreme positive G forces in any direction in excess of their limits. That would be one hell of a hard landing.

[rokky]

A320 says LAND ASAP why not MD11?

This is telling as Zimmermann was an A320 instructor before becoming MD11 lead instructor.

He should have used his A320 experience as back-up and questioned SR's overly-complex and jumbled MD11 procedures.