Challenger crashed onto highway in Naples FL

Legitimately curious…is both engines out a modeled maneuver in the sim? Digging deep here but I thought I recalled something about FFS certification requiring flight test data to model maneuvers required for training and checking and everything else being the best guess of the sim’s software. I know the NearJet sim went from meh to bucking bronco in high altitude stalls after the FAA mandated enhanced aerodynamic models for that maneuver.

No idea. The FAA signs off on all of the training program so I'd guess is modeled correctly. The aerodynamics of the wing shouldn't really change with or without engine thrust.

When UPRT became a thing, all of our Sims got stall boxes installed that apparently allowed them to operate correctly in those flight regimes and attitudes.
 
Heavily depends on the airplane and how intact it is upon water landing.
Land based airplanes CAN be certified for water landing. Has to do specifically with floating time.

Bingo. I used to fly a Part 25 aircraft that was not certified for ditching. The reason being the manufacturer did not sacrifice an airframe to determine floating & flooding.
 
I still think I’d prefer water. Not open ocean, a standard Florida lake type. Calm water. You won’t kill anyone on terra firma. Plus, less chances of the wings hitting something and ensuing fire.


Just food for thought, I guess there isn’t really a right or wrong answer. A highway full of cars is going to go bad for a lot of people that never signed up for an airline ticket.

I just remember that C172 crash in Florida(Fort Lauderdale, maybe?) a few years back when the guy had the choice between the ocean and a highway and he took the highway, actually stuck the landing, and ended up hitting a car and burning to death in the wreckage.

I'll take the ocean everytime. Worst case scenario, I'd rather drown than burn to death or blunt force injuries.
 
Digging deep here but I thought I recalled something about FFS certification requiring flight test data to model maneuvers required for training and checking and everything else being the best guess of the sim’s software. I know the NearJet sim went from meh to bucking bronco in high altitude stalls after the FAA mandated enhanced aerodynamic models for that maneuver.
Ours just sort of quit flying at impact when I did the two-out at low altitude exercise. There's probably nothing realistic or modeled whatsoever about the contact and deceleration.

That said, the flight dynamics up to that point were realistically modeled.
 
I watched the BlanCorholio video on this and he teased a second video regarding why both engines failed simultaneously when pulled back to idle due to corrosion and misrigging on the variable guide vanes (those things can be a nightmare). As a mechanic I always want to see where advice, guidance or practices fail. Both engines failing at once with no abhorrent inputs from the pilots seems statistically almost impossible, yet here we are.
 
Ours just sort of quit flying at impact when I did the two-out at low altitude exercise. There's probably nothing realistic or modeled whatsoever about the contact and deceleration.

That said, the flight dynamics up to that point were realistically modeled.

Well that Ethiopian 767 did an ok ditching considering the circumstances
 
I watched the BlanCorholio video on this and he teased a second video regarding why both engines failed simultaneously when pulled back to idle due to corrosion and misrigging on the variable guide vanes (those things can be a nightmare). As a mechanic I always want to see where advice, guidance or practices fail. Both engines failing at once with no abhorrent inputs from the pilots seems statistically almost impossible, yet here we are.
In the docket there is a bunch of stuff from GE reading salt corrosion causing the vanes to stick.

 

Attachments

Well that Ethiopian 767 did an ok ditching considering the circumstances
I’ve no interest in finding out for myself, but I would speculate that I’ve got a lot better chances of survival in this thing than in the CRJ or EMB-120.
 
In the docket there is a bunch of stuff from GE reading salt corrosion causing the vanes to stick.

I have to say I have very little experience with Challengers and their GE engines, I will say that I hated working on those engines, the only engine I hated more was the the Garret ATF on the Falcon 200, never heard of the 200 or the ATF? It was a Falcon 20 with engines off a cruise missile (the french once put afterburners on one and it went pretty fast, not real fast but pretty fast). The cowls are poorly engineered and to get to anything important you have to open the outer cowl and then open the inner cowl and it's always a filthy mess once you get where you need to go. As far as the VGVs go the problem is they live in a fairly hostile environment inside and outside the core of the engine and despite what you might suspect regarding their actuation it's often a function of the fuel control and fuel pressure is used to actuate the vanes. There's a procedure for the BR710s on the GV and above where you access the core and basically hose down the linkages with lubricant and it sucks. Because I don't know that much about the Challenger engines I'm curious to hear about how it works.
 
I have to say I have very little experience with Challengers and their GE engines, I will say that I hated working on those engines, the only engine I hated more was the the Garret ATF on the Falcon 200, never heard of the 200 or the ATF? It was a Falcon 20 with engines off a cruise missile (the french once put afterburners on one and it went pretty fast, not real fast but pretty fast). The cowls are poorly engineered and to get to anything important you have to open the outer cowl and then open the inner cowl and it's always a filthy mess once you get where you need to go. As far as the VGVs go the problem is they live in a fairly hostile environment inside and outside the core of the engine and despite what you might suspect regarding their actuation it's often a function of the fuel control and fuel pressure is used to actuate the vanes. There's a procedure for the BR710s on the GV and above where you access the core and basically hose down the linkages with lubricant and it sucks. Because I don't know that much about the Challenger engines I'm curious to hear about how it works.
Jeff Gordon had a Falcon 200 back in the day, I brought him and later his crew their rental car when they came to MKC for the Kansas Speedway NASCAR race. The redneck Air Force had all kinds of old junky or freaky airplanes back then. First time I saw a SAAB 2000 also.

I flew with someone who flew Falcon 200s and said the whole airplane is a freak. Those goofy engines and the systems had been updated to make it like a twin engine Falcon 50.
 
Jeff Gordon had a Falcon 200 back in the day, I brought him and later his crew their rental car when they came to MKC for the Kansas Speedway NASCAR race. The redneck Air Force had all kinds of old junky or freaky airplanes back then. First time I saw a SAAB 2000 also.

I flew with someone who flew Falcon 200s and said the whole airplane is a freak. Those goofy engines and the systems had been updated to make it like a twin engine Falcon 50.
My problem with the Falcon 200 was mostly because the owner of the company I worked for thought I was a fairly bright fellow and just sort of dropped it in my lap and expected me to figure it out. I'd worked on some fairly diverse airplanes over the years up to that point but I'd never been intimate with a Falcon. All of the required maintenance instructions were pretty cheap, surprisingly cheap actually. And then I found out why, the 200 AMM, WDM and any other books were just supplements to the Falcon 20 manuals that I didn't have, you have to remember this was back when microfiche was the standard alternative to an entire wall full of binders, those were dog eared as well but we didn't have a Falcon 20 so that shelf was empty. In any case the airplane was kind of a mess that showed up with no tail number from Australia, it looked nice but needed some work. We got it sorted and it was quickly sold, I suspect it headed south never to be seen again. I haven't thought about that whole situation in a long time, thanks for stirring up the brain soup.
 
Final report is out. NTSB Docket - Docket Management System

"Corrosion of both engines’ variable geometry (VG) system components, which led to theiroperation in an off-schedule position and resulted in near-simultaneous sub-idle rotatingcompressor stalls on approach, subsequent loss of thrust in both engines, and an off-airportlanding. Contributing to the accident was inadequate fault isolation guidance from the enginemanufacturer, which prevented the identification of corrosion buildup in VG systemcomponents during troubleshooting of hung start events of both engines about 1 monthbefore the accident."

Also interesting:

"According to the cabin attendant, her training did not include how to open the baggage door.She reported that she knew how to open it because, in the past, she had helped pilots loadbaggage."
 
Final report is out. NTSB Docket - Docket Management System

"Corrosion of both engines’ variable geometry (VG) system components, which led to theiroperation in an off-schedule position and resulted in near-simultaneous sub-idle rotatingcompressor stalls on approach, subsequent loss of thrust in both engines, and an off-airportlanding. Contributing to the accident was inadequate fault isolation guidance from the enginemanufacturer, which prevented the identification of corrosion buildup in VG systemcomponents during troubleshooting of hung start events of both engines about 1 monthbefore the accident."

Also interesting:

"According to the cabin attendant, her training did not include how to open the baggage door.She reported that she knew how to open it because, in the past, she had helped pilots loadbaggage."
Yup, cabinet attendant, not a flight attendant like at the airlines.
 
Final report is out. NTSB Docket - Docket Management System

"Corrosion of both engines’ variable geometry (VG) system components, which led to theiroperation in an off-schedule position and resulted in near-simultaneous sub-idle rotatingcompressor stalls on approach, subsequent loss of thrust in both engines, and an off-airportlanding. Contributing to the accident was inadequate fault isolation guidance from the enginemanufacturer, which prevented the identification of corrosion buildup in VG systemcomponents during troubleshooting of hung start events of both engines about 1 monthbefore the accident."

Also interesting:

"According to the cabin attendant, her training did not include how to open the baggage door.She reported that she knew how to open it because, in the past, she had helped pilots loadbaggage."

So is this a mx failure or a collection of errors/incompetence by multiple parties or what?
 
Final report is out. NTSB Docket - Docket Management System

"Corrosion of both engines’ variable geometry (VG) system components, which led to theiroperation in an off-schedule position and resulted in near-simultaneous sub-idle rotatingcompressor stalls on approach, subsequent loss of thrust in both engines, and an off-airportlanding. Contributing to the accident was inadequate fault isolation guidance from the enginemanufacturer, which prevented the identification of corrosion buildup in VG systemcomponents during troubleshooting of hung start events of both engines about 1 monthbefore the accident."

Also interesting:

"According to the cabin attendant, her training did not include how to open the baggage door.She reported that she knew how to open it because, in the past, she had helped pilots loadbaggage."

The baggage door is not considered to be an emergency exit (although it is accessible through the cabin) or a way to egress the airplane even do it could absolutely work in a pinch. It probably should be a part of their training.
 
So is this a mx failure or a collection of errors/incompetence by multiple parties or what?
It was stated that before it gets to this level the engine should have “hung starts” before flaming out inflight. Both engines had hung starts 25 days prior to the accident but the maint flow chart didn’t have a “check for corrosion” step until step 42 of a 58 step flow. They performed the flow chart but got the engines up and running prior to that step and the aircraft wa returned to service and flew like 50 hours since the hung starts.

The manufacture has now amended said flow chart such that it is now step 2.
 
It was stated that before it gets to this level the engine should have “hung starts” before flaming out inflight. Both engines had hung starts 25 days prior to the accident but the maint flow chart didn’t have a “check for corrosion” step until step 42 of a 58 step flow. They performed the flow chart but got the engines up and running prior to that step and the aircraft wa returned to service and flew like 50 hours since the hung starts.

The manufacture has now amended said flow chart such that it is now step 2.
I suspect this is the reason why on the Gulfstream (Rolls-Royce) engines I've worked on it was a required time limited inspection/service to access, inspect and lubricate the IGV actuation mechanism. It's an enormous pain the ass that takes a lot of time, requires special tools and at least one person who's done it. Sometimes two, because as you're lubricating the mechanism you have to actuate it, that requires a big breaker bar and a special tool, but you're fighting the fuel control. The obvious solution is to open the fuel lines to the actuator to free up the fuel and make it easier but then you'd have to bleed the entire system and ain't no one got time for that and that's not what the EMM describes anyways. So when you need to move the entire contraption you have someone pressing real hard on one end of the tool to make sure it doesn't slip off and someone else on the other end of that 48" breaker bar trying to rotate it. I actually walked away from a good paying job once because I found out this exact operation had been pencil whipped on a G-V. "New Management" had come in and were making changes, I left at the end of one day thinking we had a plan to accomplish the MX due over the next day or two (this isn't a difficult job, it just takes a lot of time to do right). I walked in the next day and found a log entry on my desk from a vendor that was not on our FAA approved list that had apparently shown up just after everyone left, done the job, and signed it off. I looked out from my office and the airplane was still exactly where it had been, all of the lifts and stands were where they had been. Then I checked the schedule, that airplane was going on a long charter that was leaving that afternoon. So I just said I didn't feel well and needed to go home. My name was on the flowchart of responsible people in our FAA approved GMM and I just walked away. I went back once, to pick up my tools and that was it. I'm not going to name names, unless they name me, then I'll tell the whole story
 
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