Another "smart pilot's trick"

[Gabriel]

A pilot of a CRJ-200 is cleared to descend and slow down.

To speed-up the process, he intentionally unlocks two red triggers, that are there to prevent that the thrust levers are inadvertently moved below the IDLE setting and towards the SHUT OFF setting, and intentionally moves the thrust levers below the IDLE setting.

The result? Simultaneous double engine shut down. Brief loss of all electric power (until the RAT kicked in).

The captain is then "surprised" that this had happened even when the thrust levers didn't reach as far as the SHUT OFF mark. It is not reported, but I can hear him saying (or thinking) "it had never happened the times I did this before".

A good reason not to give this pilot a Darwin award is because there were a bunch of innocent passengers behind. Fortunately, he was able to restart both engines thus saving the passengers (and skipping the Darwin award).

A nice outcome would have been a power-off off-airport landing (with no injuries, please). I'd have loved listening this captain's explanations.

http://www.avherald.com/h?article=41599b79/0001&opt=0

[Felipe Garcia]

Good thing they were able to restart the engines before they started cooling down and locked the core.

[Gabriel]

Originally Posted by Felipe Garcia

Good thing they were able to restart the engines before they started cooling down and locked the core.

I am not sure, but I think that the opposite happened in the Pinnacle crash.

They attempted a windmill restart to high and slow, well out of the windmill restart envelope. The engines were not windmilling fast enough and there was not enough air passing through the engine. When they tried to restart, the fuel burned too hot(*) and locked the core.

(*) most of the air that goes through the engine core is used not to burn fuel, but to mix and cool the lesser part that is used to burn fuel until it reaches an acceptable temp for the turbine.

[brianw999]

W +

[Gabriel]

Double U plus anchor?

[Evan]

Originally Posted by Gabriel

To speed-up the process, he intentionally unlocks two red triggers, that are there to prevent that the thrust levers are inadvertently moved below the IDLE setting and towards the SHUT OFF setting

At some point, we are going to have to make it a requirement that pilots understand how their plane works before they are certified to fly it. Not yet though. More people have to die first. We don't want to seem overly cautious.

[Gabriel]

Originally Posted by Evan

At some point, we are going to have to make it a requirement that pilots understand how their plane works before they are certified to fly it. Not yet though. More people have to die first. We don't want to seem overly cautious.

What do you mean? I have no doubt that this pilot knew that these red mechanical locks are there to prevent that the thrust levers are moved below the IDLE setting and that he was not supposed to intentionally release them and move the levers below that setting, and at minimum he should have imagined that there was a good reason for all that.

I don't think this case was one of lack of knowledge about how the plane works, at least not directly. This was more a pilot doing a stupid trick and knowing it was a stupid trick.

But to your point, a reader comment in AvHerlad says that this trick doesn't work anyway because the engines do not go below idle by moving the levers below idle. They just keep at idle until the levers reach the "shut off" zone. Another user mentioned that the descent rate and loose of speed implicit in the clearance wasn't much for this plane and it could have been easily achieved at idle thrust. An another mentioned that he could have very well used the spoilers instead of trying to get less thrust than the minimum allowed in flight.

From this point of view, if the above is true then a better knowledge of the plane and procedures could have prevented this either because it wouldn't work anyway or because there were other means (and legal ones) to achieve the same result.

But you would still have a pilot with the willingness of doing stupid tricks. Not this trick this time, but maybe another trick at another time. I'm not sure that any amount of training can fix that.

[W7PSK]

Originally Posted by Gabriel

Double U plus anchor?

wanchor

else wize known as wanker

british term for Fing Idiot.

[Gabriel]

Thanks for the, errr..., enlightenment?

[Felipe Garcia]

Originally Posted by Gabriel

I am not sure, but I think that the opposite happened in the Pinnacle crash.

They attempted a windmill restart to high and slow, well out of the windmill restart envelope. The engines were not windmilling fast enough and there was not enough air passing through the engine. When they tried to restart, the fuel burned too hot(*) and locked the core.

(*) most of the air that goes through the engine core is used not to burn fuel, but to mix and cool the lesser part that is used to burn fuel until it reaches an acceptable temp for the turbine.

What I don't know is if you let the engines cool down by themselves (no cooling airflow) if there would be a difference in the time it takes for all the turbine components to cool down and have short periods of core lock until everything has contracted down to normal levels. I guess I will have to wait a few more weeks to find out, now I'm really considering not dropping that High Temperature Turbine Materials course this coming semester.

Also, the fact that the Pinnacle pilots tried to restart the engines 4 or so times may have contributed significantly to the core lock.

[Evan]

Originally Posted by Gabriel

What do you mean? I have no doubt that this pilot knew that these red mechanical locks are there to prevent that the thrust levers are moved below the IDLE setting and that he was not supposed to intentionally release them and move the levers below that setting, and at minimum he should have imagined that there was a good reason for all that.

What I mean is that he should have known what THAT REASON is.

[Gabriel]

Originally Posted by Evan

What I mean is that he should have known what THAT REASON is.

Well, the rest of my post (the part that you didn't quote) adressed that, or at least my opinion on that.

[Gabriel]

Originally Posted by Felipe Garcia

What I don't know is if you let the engines cool down by themselves (no cooling airflow) if there would be a difference in the time it takes for all the turbine components to cool down and have short periods of core lock until everything has contracted down to normal levels.

I hope and guess that the design takes that into consideration to prevent it. If you accidentally shut down an engine you should be able to attempt a restart as soon as you are within the required envelope.

That said, I think there is a "waiting" period between an unsuccessful restart and the next attempt.

[Evan]

Originally Posted by Gabriel

Well, the rest of my post (the part that you didn't quote) adressed that, or at least my opinion on that.

So you would agree that the pilot clearly didn't understand how the throttle works in this position, as he was attempting a trick that wouldn't have worked anyway?

[Gabriel]

Originally Posted by Evan

So you would agree that the pilot clearly didn't understand how the throttle works in this position, as he was attempting a trick that wouldn't have worked anyway?

I don't know. That's what the AvHerald reader said.

But the core of my opinion is that, in any event, the pilot was INTNTIONALLY doing something he KNEW he was NOT supposed to do. And no airplane knowledge can justify that, unless it's an emergency and the pilot judges that doing that will save lives.

Say that the AvHerald user is wrong, and that the pilot was right, that in fact if you move the levers below idle but above shut-off gives you a reduced thrust below idle. Are the pilot's actions any more acceptable?

[Evan]

Originally Posted by Gabriel

I don't know. That's what the AvHerald reader said.

But the core of my opinion is that, in any event, the pilot was INTNTIONALLY doing something he KNEW he was NOT supposed to do.

And why was he doing this? I think it is because certain pilots, having basic airmanship skills but lacking in depth knowledge of the aircraft functions, believe they can flaunt the rules and fly by the seat of their pants, so to speak, (see 3WE) and so they improvise themselves into these situations. Some pilots will follow the rules and some think they are above them, due to their basic skills. If these pilots knew the reasons why these things are rules, they might not try to work around them.

[Gabriel]

Originally Posted by Evan

And why was he doing this? I think it is because certain pilots, having basic airmanship skills but lacking in depth knowledge of the aircraft functions, believe they can flaunt the rules and fly by the seat of their pants, so to speak, (see 3WE) and so they improvise themselves into these situations. Some pilots will follow the rules and some think they are above them, due to their basic skills. If these pilots knew the reasons why these things are rules, they might not try to work around them.

I don't agree that this case applies here.
Attempting to put the plane (or its engines) outside the approved envelope has nothing to do with airmanship or thinking that one's skills are above the rules.

Again, say that the AvHerald user is wrong, and that the pilot's knowledge was right, that in fact if you move the levers below idle but above shut-off gives you a reduced thrust below idle. Are the pilot's actions any more acceptable?

I compare this incident with things like:
Let's keep take-off thrust past the 5 minutes limit. We know the engine can withstand it. That way we'll for one oh' it faster.
Let's fly a bit faster than Mmo. We know there is margin above it and we'll reach home sooner.
Let's shut down one of the engines for our descent from 410 until we start the approach, so we'll recover the extra fuel burned with the previous two tricks.


Side note (and no, I don't want to start a discussion on this): I don't think (but I am not sure) that 3we ever proposed using the basic airmanship technique in place of the approved procedures. Just that using basic airmanship techniques was safe (I add, not necessarily as safe as the approved procedure). I also mentioned that not following the UAS airspeed procedure is not enough to explain the bizarre reaction of the AF pilot that was way contrary to basic airmanship by so much.

[snydersnapshots]

Well...I'm guessing everyone junior to this moron moved up a number...

[3WE]

Originally Posted by Evan

having basic airmanship skills but lacking in depth knowledge of the aircraft functions, believe they can flaunt the rules and fly by the seat of their pants, so to speak, (see 3WE) and so they improvise themselves into these situations.

Umm no, Evan.

General fundamental knowledge with no type-specific training would tell me two things.

1) It's a bad idea to flip up the red switches. (Basic fundamental rule: Red = Bad)

2) To little fuel usually means the motor won't run.

(And guess what...fundamental rule #2 works in a CRJ, Cessna 172, your car, your lawnmower, and a coal-fired steam locomotive- and while I've driven cars, lawnmowers and 172s, I think it's a bad idea to almost totally cut off the fuel to a CRJ and a locomotive (but no training there either).

Nice try, thanks for playing.

[3WE]

Originally Posted by Gabriel

I don't think (but I am not sure) that 3we ever proposed using the basic airmanship technique in place of the approved procedures.

There are several threads where I am quoted as saying that I want my pilots to know the procedures cold and know the airmanship cold.

However, a number of puppy mill curicula have been criticized for "teaching procedures only, and how to pass the test" at the expense of fundamental airmanship skills.

"At the expense of" are the magic, and critically sad words.

Then recurrent training is sometimes criticized at emphasising procedures at the expense of fundamental airmanship.

...then we have pilot behavior in a number of crashes that suggests a decent knowledge of procedure and a lousy knowledge of airmanship.

The airbus pilots displayed bad knowledge of both. But I find it sad that fundamental things they might have learned in a 172 and then transferred to a turbo prop and transferred to an RJ and transferred to short domestic routes as they advanced as a pilot- the exact same things- could have saved the day in the fancy, international airbus flight.

Evan- as evidenced in this thread, displays a significant interest in procedures and a significant disdain for fundamentals.