"Reduced Thrust" cause for Comair crash?

[RP 04]

I don't thing they were interested in a BFL, beeing able to get airborne was probably closer on their mind...

 

[svcta]

Last time I flew a CRJ we were using flaps 8 every chance we got(as a policy); kept more air moving throught the powerplants @ rotation because of the higher speeds. When that thing was heavy and you were flexing I remember rolling for about 2 days before V1. I recall burning up 5 or 6 thousand feet pretty easily.

 

[Fearless Tower]

Last I read they were at 137kts when they exited the runway. Flaps 20 t/o on the 50,000# card they should have been real close to flying. I definitely wouldn't say there was no way that they could have made it.

The only report the NTSB made regarding speed was that the max speed they reached before crashing was 137 kts. They didn't state they were at 137 when they left the runway (or the grass).

 

[wmuflyguy]

Last time I flew a CRJ we were using flaps 8 every chance we got(as a policy); kept more air moving throught the powerplants @ rotation because of the higher speeds. When that thing was heavy and you were flexing I remember rolling for about 2 days before V1. I recall burning up 5 or 6 thousand feet pretty easily.

Different company different policies. Flaps 8 take-off gives you a bit better climb performane when you lose an engine, but a longer t/o roll. Comair doesn't fly out west to much anymore, we have flaps 8 procedures for when they are needed and they are all at high altitude airports.

 

[PunchTheClown]

Either way it dosent matter. The flex thrust would have been fine for 22 which is what they were set up and planning for. This lawyer is just being a lawyer. He is definitely a scumbag and should rot for it. Its not going to be management the eventually destroys this industry. Its going to be the sorry excuse for human being lawyers.

 

[rickair7777]

I think it was closer than some people think. Academically speaking I think a static runup, full power, flaps 20, and agressive rotation could have accomplished a 3500' T/O...of course this has no bearing on the real world events because they would have had to know in advance, in which case they would have just used 22.

There have been many airline diasasters where folks have been able to replicate the events in a sim with favorable outcomes...but usually only after multiple attempts and of course with advance knowledge of the triggering events.

 

[yournextFO]

Unfortunately I don't think that a CRJ200 with 50 people on board would take off from a 3500' runway even if you firewalled the power from the start of the takeoff roll.

I was in the sim today and we tried it...at 50000 lbs, 22 C, 3500 feet is enough runway to get in the air at either flaps 8 or 20 from a rolling takeoff. We were, however, rotating at the _end_ of the runway and at very low altitude (10-30 ft) for several hundred feet beyond the threshold. It wouldn't take much of an obstacle at all. Factor in that the sim usually performs better than the actual plane, it was dark, no runway lights, and they weren't prepared for it, well, we all know it ended in tragedy.

 

[xjhawk]

what ifs....i bet.......you know what we do.......they prob did this.......they should have done........leave it be, let the investigators do their thing, we wil all find out eventually, morn for those lost, and learn from this even and let it be, and pray for those who lost love ones. enough said

 

[spiffomatic]

this lawyer is a jacka$$ - he's just going for the dollars, and they reside with Delta, Bombardier, etc.

Reduced power (per company policy) versus full power could have made a difference, but it was not the proximate cause of the accident. The controller's sleep or lack of sleep could have made a difference, but it too was not the proximate cause of the accident.

The primary reason there are several dozen people dead was (at least, based on available information so far) that the pilots just flat out picked out the wrong runway.

You can talk "chain of events" all day long, but everyone takes off from a field before the tower's open at least sometimes. There's noone holding your hand there, but it's considered safe enough for part 121 operations. Final authority and final responsibility for this sort of error resides in the cockpit. None of us are immune to this sort of error, and you've got to be ever vigilant, (and perhaps sometimes a little luck doesn't hurt) to keep it safe each and every flight.

may they all rest in peace.

just my humble opinion.

 

[CherryBomb]

You sir, are a dork.

Sorry Hawker "dude", I believe you're wrong. Like the other guy said, the rate of thrust is NOT linear. In fact in the higher rpm ranges thrust is exponential.

Dont believe me? Look at your fuel flow and compare the difference between 95 percent and 100 percent...


But bottom line, let the investigators do their jobs. RIP comrades....

 

[Black Hawk]

The engines were set to 90% N1 and stayed that way until the FDR stopped recording. In order to use a BFL of 3500' the CRJ 200 would have to weigh 33,000.

That's pretty surprising. No change in thrust? They must not have seen it coming.

 

[Gorilla]

That's pretty surprising. No change in thrust? They must not have seen it coming.

I don't know this AC, but didn't someone say before there is no FADEC-type control on this bird? Not being able to firewall with confidence makes guys tend to not manipulate the throttles in such a setting.

I hated the MD-80 for this very reason. The 737-800, and most Boeings, are great in this regard. Slam 'em to the stop, no worries.

 

[Sam Snead]

I don't think the pilots' response to the 'we're out of runway' problem would have caused either of them to firewall the thrust levers.

My reasoning is that the only non-FADEC simulator scenario that calls for 'radar power' is windshear.

Unfortunately, confusion probably reigned as the airplane went from asphalt to grass. My guess is that they only realized there was a problem when the wheels started rumbling over the grass. Given the lighting conditions and the circadian time of day, they didn't see the red end lighting, or if they did they did there was little or no deceleration.

This all assumes the CRJ model in question is non-FADEC. Anyone?

I've made bigger mistakes but been a lucky SOB.

 

[belchfire]

Most airplanes will lift off at significantly lower speeds than we use in calculating performance. We accept longer takeoff runs in order to build speed that should provide single engine performance in the event of a failure.

Someone mentioned windshear. While I have never had an on the runway windshear encounter demonstrated in the sim (only on departure or approach) the recommended proceedure is firewall thrust and rotating past the target pitch. These are last ditch methods where immediate threat overrides meeting calculated engine failure performance requirements.

Since we don't have the engineering data there is no way to calculate if extream measures applied soon enough would have got the airplane in the air.

The point is that even with max thrust I don't think that there was any way that any RJ could have met accelerated stop requirements on that runway.

 

[Airboss]

I don't think the pilots' response to the 'we're out of runway' problem would have caused either of them to firewall the thrust levers.

My reasoning is that the only non-FADEC simulator scenario that calls for 'radar power' is windshear.

Unfortunately, confusion probably reigned as the airplane went from asphalt to grass. My guess is that they only realized there was a problem when the wheels started rumbling over the grass. Given the lighting conditions and the circadian time of day, they didn't see the red end lighting, or if they did they did there was little or no deceleration.

This all assumes the CRJ model in question is non-FADEC. Anyone?

I've made bigger mistakes but been a lucky SOB.

The CRJ-100/200 are non-Fadec. The CRJ-700 on have fadec with a T/O detent on the thrust levers

 

[Tri-holer]

As some people have said, it is probably possible to yank the plane off a few knots early IF you knew what you were facing. From the lighting conditions (runway unlit and dark) their first indications of anything wrong would probably have been the dashed lines disappearing and wheels hitting the grass. A little late to be figuring out what kind of heroic measures to be taking.

 

[Patriot328]

Did they actually roll off the runway into the grass before getting airborne? From the pictures I saw, it looks like they got in the air over the runway but then clipped a grass berm with the gear about 2-300 feet past the end of the runway...

 

[PURPLEHAZE21]

Guys,

Were talking about Lawyers.......Don't get sucked in to the Vacuum !!!!!!!!!

 

[Syllogism]

If the crew planed on using runway 22 (which they did), than reduced thrust was NOT an option. For 3A-1 engines, the maximum weight authorized for a reduced thrust takeoff is 47,000lbs - regardless of temp. For 3B-1 engines, reduced thrust IS permitted off of runway 22 at weights as heavy as 50,100 pounds, but not if the temperature is 23 degrees or warmer. The temperature reported on the ATIS Sunday morning was 23 degrees. Normal thrust was required from 5191 in either case.

We have been told by the NTSB that the lights for runway 26 were not on. As a result, it wouldn’t be possible for the crew to see that they were at approaching the end of the runway until their landing lights started to shine the non-reflective grass blades (probably about 200 feet from the end). Consequently, it is unlikely that they could see the grass until they were about 3 knots from V1. If they could have visually detected they were on the wrong runway, the crew could have stopped the aircraft (while remaining on the runway pavement) as late as 110 knots into the takeoff roll. Jamming the thrust levers to the stops (full power) as early as 100 knots wouldn’t have saved them. The laws of physics wouldn’t have permitted it.

More stuff...

The big "26" painted on the short runway is located so far back that the only pilots who will ever see the marking are those who are planing to use it for landing. That’s stupid and the marker should have been further forward. That would have made the marking useful for ALL pilots - including the pilots operating flight 5191. What’s more, the big "22" that’s painted on the long runway cannot be seen unless you back-taxi the aircraft. That’s because KLEX has a "new intersection" as a result of the "new taxi route". Additionally, the runway analysis data for RWY 22 is only accurate from a full length takeoff. Though I do not know for sure, I doubt a full length takeoff was attempted. If a full length takeoff was briefed (or at least attempted), I think the crew would have saw the big 26 painted at the end of the runway. Presumably, it would appear as though they thought they were performing an un-authorized intersection takeoff even though it was a near full-length from runway 26. If they had attempted a full length, they would have likely saw the 26 (more taxi briefing stuff).

Of course these are just "little things" individually but, a lot of little things are what add up to an accident eventually.

 

[belchfire]

Guys,

Were talking about Lawyers.......Don't get sucked in to the Vacuum !!!!!!!!!

Well yeah, they got OJ off and most politicians are lawers-which explains alot!

 

[EdAtTheAirport]

Why doesn't anyone ever blame juries???

 

[surplus1]

I've been reading, and reading, and reading, and I've seen all sorts of hypotheticals about how this might have happened.

I heard the NTSB peson say (on TV) that there was verbalization between the pilots about the runway lights being out.

But, no where at anytime have I seen anyone of you pilots question or comment about why this airplane was taking off on an unlighted runway.

I have to ask: Is that something that you folks consider as a "normal" thing you do? A routine operation?

 

[El Ocho]

Training should be addressed

Over at PPrune there is an old dude that said this: he had a sim instructor that used to pull another aircraft onto the runway when they were about V1 - 10 on the takeoff roll.

The instructor taught them to slap down full flaps. Their aircraft would balloon into the air and barely climb, but they would make it.

Sounds silly, but when you've run out of all other options....

I've been saying for years we are inadequately trained for various extreme emergencies.

Same is true of AirMidwest B1900 crash due to misrigged elevator. (Which granted i've NOW seen some similar senarios in sim training.)

There are strategies that could be applied. Maybe with unlikely success given the gravity of the situations, but it boggles the mind to think that commercial 121 passenger carrying pilots, and ATP qualifications do not include extreme emergency responce options. Why is there only one sim guy, for one company, all on his own, training about potential extreme emergency responce options? You know, not like the usual memory items stuff, but when it really is time imperitive to do just the right thing to survive?

And you know what, maybe what we need is a clever lawyer to bring a suit about the limitations of part 121 emergency training for that to improve.

(For you sensitive types that say no talking about anything before the final NTSB report, I am not questioning the pilots, or blaming them! I'm looking at the system they operate in to the best of their abilities and knowledge.)

 

[surplus1]

Somebody please reply to #52

 

[wmuflyguy]

I've been reading, and reading, and reading, and I've seen all sorts of hypotheticals about how this might have happened.

I heard the NTSB peson say (on TV) that there was verbalization between the pilots about the runway lights being out.

But, no where at anytime have I seen anyone of you pilots question or comment about why this airplane was taking off on an unlighted runway.

I have to ask: Is that something that you folks consider as a "normal" thing you do? A routine operation?

I wouldn't consider it normal, but it depends what was notamed out of service on runway 22. If it somewhat agreed with what they had expected to see it would take a while for the mind to sort out what is happening.

I wouldn't call operating to a runway with no vertical guidance (no vasi/gs) and almost all the lights inop a normal operation, but after talking to some pilots that had recently flew into lex, that was what was going on at lex.

 

[DrewBlows]

Somebody please reply to #52

I've never done it, but I could think of a senerio which I might. I haven't read anything that difinitively stated that the runway lights were out, I also haven't read a transcipt of the CVR.

Definately not routine, but properly briefed, not unthinkable.

 

[172driver]

Surplus,

My speculation, as posted on another thread, is that it looked lighted until they were well into the t/o roll.

There are rwy lights for 22 on either side of 26. Wish I could draw a picture, but maybe you can imagine it...there are probably four lights, one on each corner of the intersecton of the two rwys, which could appear to be the first two sets of lights for the rwy they lined up on (actually 26, but 22 in their minds). Because of the upslope/downslope at the beginning of 22 (which the crew was no doubt familiar with), having only two sets of lights would seem like a normal picture, at least until they had rolled past the actual rwy 22 and had no lights out front.

I believe the CVR reflected that they commented on the lights during the t/o roll, not before, as you would expect if the rwy had appeared to be unlit. That's my take on it.

 

[DrewBlows]

I believe the CVR reflected that they commented on the lights during the t/o roll, not before, as you would expect if the rwy had appeared to be unlit. That's my take on it.

Where did you read the CVR transcript?

 

[Dix-Bag]

I hated the MD-80 for this very reason. The 737-800, and most Boeings, are great in this regard. Slam 'em to the stop, no worries.

I've never tried it (and don't plan to), but I've heard on the MD-80 with 219's (or probably 217's for that matter) you can firewall the thrust levers and the fuel control should prevent the engines from (for lack of a better word) exploding. It works fine in the sim anyway. I'd assume it will significantly reduce the life of the things, but nevertheless, I'd deffinately slam them up there if need be.

Have you heard differently Gorilla?

 

[172driver]

Where did you read the CVR transcript?

The NTSB released a couple details shortly after the accident.