OK -
Cannot remember details (otherwise I’d link to NTSB report), but:
2 aspiring pilots land jobs as pilot and co-pilot of your basic biz jet.
Plane has a rated max operating altitute of 41000.
Young jet jpckeys have never been that high.
They get the keys for a re-positioning flihgt (no passengers), and decide to see what FL410 looks like. ATC clears them.
I believe the old term is flame-out. Engines stop. They cannot restart, and crash. Plane destroyed, 2 dead.
Q:s
Why coulld a modern jet NOT be restarted (at a lower altitude?)?
Why, with 41000 feet to glide, could they NOT make a controlled landing? Are hydraulic systems absolutely dependant on the engines turning?
It was Pinnacle 3701. The engines could not be restarted because the pilots did not follow the correct procedures and maintain the airspeed necessary for a restart. One could place some blame on the regional airlines for providing inadequate training to their pilots, but to put it bluntly, the two pilots here pretty much acted like idiots for the whole flight.
There was a defect in the engine design which rendered them unstartable after they flamed out. Which they should not have done in the first place, but for another design defect.
Landing a jet from a glide is not something anyone practices. Over something large and landable-onable like Edwards AFB dry lake you’re likely to be able to find a long flat surface in front of you when the altitude runs out. Over generic Midwest terrain, it’s much more likely you’ll overshoot or undershoot an airport by miles.
In their case, they spent most of their altitude following the restart procedures which were doomed to fail (unbeknownst to them). Once they gave up on restart, they were not well-located to get to an airport.
My bottom line:
Those two guys were not God’s gift to aviation, but a lot of lay commentary has made them out to be total bozos. Not really.
I disagree with the essence of this statement. A nominally trained pilot should be able to dead stick a plane in unless there is a loss of control surfaces. The plane wouldn’t care if the engines were lit. Air speed is air speed and at 41,000 feet you should be able to land just about anywhere there’s an airport.
If you can cross-control a 757 on an abandoned airport or land an Airbus on a river without power I don’t see why this plane could not have landed safely.
I’m sure you’ve forgotten more about planes and flying than i’ll ever know, but the NTSB summary linked above seems to take a somewhat less sympathetic view of the pilots than you do.
I assume you mean the Gimli Glider for the first and that plane had a Ram Air Turbine that deployed in the event of total loss of engine power. The plane’s forward airspeed spun the turbine which provide just enough hydraulic pressure to control the plane.
In the case of the second I assume the plane’s auxiliary power unit kept hydraulic pressure to control the plane despite the loss of both engines.
I do not know if that Bombardier 600 had such features.
Besides, sounds from above like the pilots used their altitude to restart the engines. Had they chosen to deadstick in from 41,000 maybe things would have turned out better.
Nitpick: the CL-600-2B19 is a CRJ-200 (regional jet). I’m only pointing this out because “600” is more closely associated with the Challenger 600 and its variants, a business jet. They all share a type certificate, but it can lead to confusion, so I thought I’d point it out.
I’m almost certain that the APU in the 2B19 is linked to the hydraulic system, and in any case, the RAT can provide enough power to power the control surfaces. But I am not an engineer (yet), nor do I know the inner workings of these planes (…yet?)
I made the assumption that they had control of the aircraft based on the original description of events. It appears they tried to restart the engines with an APU so that tells me that had the power source necessary. And instead of using altitude to restart like they should they used the APU’s.
Like most aviation crashes this one was a series of events leading up to it. I find it difficult to believe that even a low time certified pilot didn’t know and understand the concept of wind-milling an engine as part of the restart process. I don’t understand why they go into core-lock but I would only have to hear this once in a sentence to remember it on a conceptual basis.
What I would expect from a crew of 2 is for one person to fly the plane and declare an emergency while the other pulls the manual out to get the restart checklist. This puts a regional radar center in the position of active navigator to the closest airport. The goal, if the engines can’t be restarted, is to make a long overshooting final so the pilot can dirty it up as needed to hit the numbers. If there isn’t an airport within reach then they need to know plan-b as soon as possible. Any restart needs to be done en-route to the emergency landing point.
My guess is that they didn’t want to get caught doing something foolish and risked safety to save their careers.
<possible nitpick> If you meant the Gimli Glider, Air Canada 143, it was a 767. Just finished watching a cool re-enactment on Canadian Discovery channel. </possible nitpick>
Can anyone please explain or give a link to what “core lock” means in a nutshell?
Stick shake and pusher (shake = the airplane’s warning you that you are about to stop flying. Push - it forcefully takes the stick from you and puts the airplane’s nose back down where it belongs) 3 times. Each time, out hero, upon being given the stick back, pulls it back up. that is just scary - that twit should not have been allowed to operate a kite.
BUT - FL 410 at last! We made it! Yea! Rah!
The plane is going 160 kts (approx 180 mph). At 41,000 feet. Pssst - you stopped flying a couple of minutes ago - you’re coasting!
I have only a vague concept of how a jet works, but: if you need 300 kts to windmill restart - 160 is Probably a little low…The truly scary part - the guy in the LEFT seat is surprised that the plane won’t hold 41,000 - it starts dropping, trying to get airspeed up. You know what comes next - pull the stick back! I want FL 410!
Gee, the engines quit. I wonder why…
I understand the “Hell, I’ve done dumber things and survived…” mindset, but to have this little understanding of “airplanes need air to fly” + “at 41,000’ MSL, the air is REALLY thin”. Incredible
NTSB concludes there were either 6 or 7 airports available within gliding range
Did GE address the core lock problem, or is it still an issue for Challengers and CRJ100/200’s? Reading the NTSB report I see that Bombardier has a screening procedure for engines, and a fix in the case that the engine doesn’t pass the screening. Surely GE should have also addressed this?
Do the other variants of CF34’s also have the same core lock problem? -8 & -10?
Cheers!
NB
I’d WAG that remembering what core lock is, and that it can occur and the basic mechanisms of how it happens is probably pretty easy. Remembering the flight conditions, aircraft configurations, engine conditions etc specific to a particular type of aircraft/engine is probably much harder.
I also WAG that even if the CF-34 variant engines are still subject to core lock, under pretty much any operating condition that can be considered even vaguely “normal”, this type of engine failure has been shown to not occur. Pretty extreme flight conditions are used to qualify and certify aircrafts and engines.
Odds are very very good that GE was involved in developing any service bulletins/airworthiness directives/modifications etc that needed to be done to these engines. Both Bombardier and GE might have issued instructions to owners/operators/maintenance centres, or Bombardier did on behalf of both, since they are the final manufacturer of the aircraft as a whole.