RJ Crash Prelim

[Oakum_Boy]

That's stretching it a bit, not to mention Monday Morning Quarterbacking. There is absolutely NOTHING wrong with having this aircraft (or any other certificated for it) up at FL 41,0. To suggest that it is otherwise is to say that the manufacturer, test pilots, and FAA (not to mention the thousands of us who have safely taken the aircraft to that altitude) are somehow less knowledgeable than you are... I wouldn't go there if I were you.

Not being practical? Many times that is correct, as are the other things you mmentioned there (with the exception of TAS deteriorating - that only happens as a function of a deteriorating IAS); sometimes the conditions (weight, temperature, and available thrust) just don't make sense to stay there, but sometimes they do. Been in both situations, sometimes you stay, sometimes you gotta give it up and go lower. Same thing in the Lear up at 51,0...

Not what I was talking about! For a given Mach number, TAS decreases with altitude. Furthermore, the Mach you can achieve at high altitudes is not great. CRJ's have the best combination of performance in the high 20's:

1. They can achieve .77 mach,
2. .77 Mach at 28000 feet is much faster than .77 mach at 41000
3. CRJ-200 Can't really do .77 Mach at higher FL's.
4. Fuel burn at 28000 feet is relatively low, compared to the TAS that you can get.

Edited for spelling, and format.

 

[Mike15601]

Food for thought from a previous incident.... Date: 20 MAR 1994
Time: 00:36 CST
Type: Canadair CL-601-3A Challenger
Operator: Crystal Aviation
Registration: N88HA
Msn / C/n: 5072
Crew: 0 fatalities / 2 on board
Passengers: 0 fatalities / 0 on board
Total: 0 fatalities / 2 on board
Airplane damage: Written off
Location: Bassett-Rock, NE (USA)
Departure airport: Burlington International Airport, VT (BTV)
Destination airport: Long Beach Municipal Airport, CA (LGB)
Narrative:
Both engines lost power at FL410; forced landing in a field, striking an irrigation structure and trees. Improper refueling by FBO personnel at Lawrence, MA caused the Challenger to depart with water contaminted fuel.

 

[Lear70]

Mike, the info you posted had been up on another thread, but fuel contamination doesn't seem to be a factor here... lots of reasons why, but the main one is that during the double engine failure, the right one got so hot that it damaged it (probably so badly that it wouldn't have restarted), which means (more than likely) that the fuel going in was burning just fine (too much fuel, not enough cooling air = extreme high temp).

Oakum, the generalities you posted on Mach .77 only work if you assume a TP level of 28,0. As long as temperature continues to decrease with altitude, a constant mach number will result in a higher TAS with a higher altitude. It only stops doing that when the ambient lapse rate stops.

And Mach .77 at 41,0? H*ll, we're lucky to get .70 out of the thing that high. Our standard cruise speed is .74, and although I'd be trying to go MUCH faster to have the airflow over the wing (resultant lift) to get higher, it may have bled off to .74 or .70 to get that last 4,000 feet but we'll know more in a month or so about that.

I personally like FL 31,0 and 33,0 in this aircraft for the best combination of fuel burn and TAS, and she'll do .77 all day long at those altitudes if you keep her speed up in the climb.

 

[acaTerry]

You mean Mr. Red FAce? Yes it is if we are thinking of the same guy

 

[comrcap]

My guess is that they stalled the airplane and both engines flamed out. The rj-50 is a pig at FL410, even if empty. That is why Comair has a min speed limitation (climb) for our rj's. We've had a couple of incidents a while ago where the aircraft was allowed to go below the green line and get on the back side of the power curve. Stick shaker and all the rest. No flame out though, thank god!

 

[efiscompmon]

Of course, Express I refused all offers of technical assistance and acquired knowledge from CMR (both CMR mgmt and Alpa) when we got our jets in 2000. Better to go it alone with our memphian inferiority complex and re-invent the wheel with our FSI manuals. I have never been privy to a min speed limitation--boy would I be peeved if that is a contributing factor in this investigation.

Can't help but wonder if SAFETY could have been enhanced by chatting with the world's largest operator of the type. I'll put that SQUARELY on Jon Y. and Santi L.'s shoulders.

I wonder how much the new "fuel policy" had an effect on the decision to be at 410.

So let's review--incomplete training, knowledge transfer blocked by management arrogance, intimidation in flight planning and fuel burn. Sounds like pinch-a-nickle! No wonder Phil T. is the RAA apologist of the year. These muppets couldnt manage a bake sale.

The irony here is that SOC is _still_ trying to dx illegally with questionable performance. "Hey, I know it's 8C and precip; would you consider taking off without anti-ice so we can make our numbers?"
"Uhhh. No. It's a limitation."
"No, it's a switch, just switch it off Captain."
Friggin unbelievable. Would be funny if people weren't dead.

I think Aaron says it best with the company motto of "Never Compromise Savings!"

 

[Oakum_Boy]

.
As long as temperature continues to decrease with altitude, a constant mach number will result in a higher TAS with a higher altitude. It only stops doing that when the ambient lapse rate stops.

Not trying to start anything here, but lets talk about this. If you're flying a constant Mach#, your TAS DECREASES with altitude. For example, if you're flying Mach 1 at sea level, that means your TAS equals the speed of sound, which at sea level is 761 MPH. Now, go to FL410. Mach 1 at 410 is 660 miles per hour. Above the Tropopause, ambient lapse rate stops, yes. But, warmer temperatures will require an increase of thrust to attain a particular Mach number. That's why above it, jets don't perform as well in terms of fuel flow. I think you're thinking of constant IAS which with altitude results in higher TAS. If fly with some people who think that's the way Mach works because the only example, unless you've been schooled properly, is when climbing at a constant IAS, then trasitioning to Mach. Until you transition to Mach, your TAS is increasing with altitude. Should I be scared when an experienced jet driver doesn't know this?????? Anyone care to jump in on this subject?????

 

[Lear70]

Oakum, no need to get personal or combative, your "Should I be scared..." comment is uncalled for.

I disagree with your assertion, but we'll put your theory to the test in ACTUAL flying conditions when I start my two-day this afternoon.

 

[DirkkDiggler]

I disagree with your assertion, but we'll put your theory to the test in ACTUAL flying conditions when I start my two-day this afternoon.

It's not an assertion. It's a fact. You can look it up an any flying book that talks about high performance jet aircraft. You guys need to read some books so you'll understand a bit more about the things you deal with everyday at work.

 

[Oakum_Boy]

Oakum, no need to get personal or combative, your "Should I be scared..." comment is uncalled for.

I disagree with your assertion, but we'll put your theory to the test in ACTUAL flying conditions when I start my two-day this afternoon.

Yes, it was uncalled for. Sorry.

 

[405]

efiscompmon-

FLG3701 was a Part 91 reposition (not a maintenance ferry as some have assumed) flight which means there wasn't even a requirement for anyone in the SOC to do a "release" or paperwork for the flight. We do that as a courtesy for you guys. The dispatcher who did the paperwork filed them at FL330. HE DID NOT, I repeat, DID NOT FILE THEM AT FL410. Why the crew went to FL410 is still unknown but I assure you it wasn't because they didn't have enough fuel for FL330.

Fuel policy was no issue here, sir.

By all means, PM me with any other 9E SOC concerns you might have.

 

[hmmm]

They went to FL 410 because it is certified for FL410 and they met the requirements in weight and temperature in accordance with the climb capability chart in the performance section of their FCOM page Per-51 and in line with the preface of their FOM that says seek the most efficient operating practice requesting "2. maximum efficiency 4. maximum economy for our flight operational activities" listed under company objectives page 2 in the "FOM Preface" in the front of the book.

Hey Dispatcher ; You have the FOM and FCOM in front of you at your desks. Why don't you guys open them up and read them once in awhile instead of sitting around between desk duties and telling jokes and B.S.ing. We know not all of you at the desk are like this. If your not then, don't take offense. But hanging around with you guys once in awhile and then talking to each other out on the line, that is what we pilots that have come around down there saw. Either read the book or don't complain when we ask for something you don't understand. Speaking out of frustration of people who don't take the time to learn how to do their job well sorry if you're offended.

 

[Crossky]

Of course, Express I refused all offers of technical assistance and acquired knowledge from CMR (both CMR mgmt and Alpa) when we got our jets in 2000. Better to go it alone with our memphian inferiority complex and re-invent the wheel with our FSI manuals. I have never been privy to a min speed limitation--boy would I be peeved if that is a contributing factor in this investigation.

Can't help but wonder if SAFETY could have been enhanced by chatting with the world's largest operator of the type. I'll put that SQUARELY on Jon Y. and Santi L.'s shoulders.

Sorry to hear that. Our company limits the climb speed to minimum Mach .70. We've had one high altitude speed problem incident I know of. The fleet manager posted to us that according to our Mach .74 climb chart, that aircraft would've been limited to FL380 (w/ approx 9K lb full). We are now indefinitely restricted to FL380 as well.

 

[Lear70]

Well, I dug out "Fly the Wing" and looks like you guys were both right; I hadn't read that since college, good refresher stuff... then I tried it tonight just for giggles to see what the "Real World" loss of TAS is.

Achieved Mach .74 climbing through 29,0 and held it climbing 500 fpm to 33,0.

TAS at 29,0 Mach .74 SAT -35 = 436 KTAS
TAS at 33,0 Mach .74 SAT -36 = 435 KTAS

I'll try it going back to DTW in the morning and on my 5 leg trip Wednesday but I'm pretty sure I'll have the same result. Maybe the difference is more drastic between 33,0 and 37,0 (not that I'll be going that high - don't have any legs long enough for this dog of an aircraft to get there), but from what I read the TAS curve with a constant mach # is pretty linear, although I didn't go through the long math explanations in the book to decipher that info.

Diggler, given your experience I don't think you have any grounds to be telling us what we should and shouldn't be studying... just a thought.

Hmmmm, go easy on Jay. He's one of the better guys we have down there and given that one fuel comment directed at the SOC regarding this event (which we all know probably wasn't a factor) and the other event which we know DID happen but certainly not from Jay, I'm not surprised he got a little defensive... I probably would too.

Actually, I haven't had a problem with fuel in quite a while now, so the new fuel policy is actually working out for me (most of the time). To tell the truth, half the time they're giving us alternates we don't need which adds to my personal "comfort level". (Never mind that the alternate weather is often worse than the destination - couldn't resist Jay!)

 

[Singlecoil]

Achieved Mach .74 climbing through 29,0 and held it climbing 500 fpm to 33,0.

TAS at 29,0 Mach .74 SAT -35 = 436 KTAS
TAS at 33,0 Mach .74 SAT -36 = 435 KTAS

I'm not sure I'm following what you're trying to prove there. The speed of sound is solely a function of air temperature, not pressure altitude. In your two examples, the temperature is almost the same, therefore the TAS is almost the same given the same Mach speed. The hotter the air, the higher the TAS for a given Mach speed.
What you are more interested in as far as keeping the plane in the air in this case is IAS, no? That's a seperate issue than the ratio of Mach to TAS. The ratio of Mach to TAS is independent of altitude, whereas the ratio of Mach to IAS (speed of the air over the wing) is not.

 

[172driver]

That's stretching it a bit, not to mention Monday Morning Quarterbacking. There is absolutely NOTHING wrong with having this aircraft (or any other certificated for it) up at FL 41,0. To suggest that it is otherwise is to say that the manufacturer, test pilots, and FAA (not to mention the thousands of us who have safely taken the aircraft to that altitude) are somehow less knowledgeable than you are... I wouldn't go there if I were you.

Diggler, given your experience I don't think you have any grounds to be telling us what we should and shouldn't be studying... just a thought.

Hey Lear, I think you ought to reopen that book and actually read it this time. Diggler's profile really doesn't state his experience level, which you insulted. Oakum may or may not have as much time as you. I certainly don't, but I will venture that our understanding of this subject is far more complete and accurate than yours. Before you go out and 'perform these tests' with people in the back, you may want to read and understand why you are getting these results.

And Mach .77 at 41,0? H*ll, we're lucky to get .70 out of the thing that high. Our standard cruise speed is .74, and although I'd be trying to go MUCH faster to have the airflow over the wing (resultant lift) to get higher, it may have bled off to .74 or .70 to get that last 4,000 feet but we'll know more in a month or so about that.

.70 at FL410 on a standard day will give you an IAS close to 200 kts. Waaay too slow for me to feel comfortable, especially with no remaining thrust. I am making no remarks about the accident, only pointing out the fact that at least one highly experienced captain seems to feel comfortable at these speeds. FL410 is probably not the place to be learning about it.

Ignorance is one thing, but insulting others due to that ignorance is another. Don't throw stones if you live in a glass house.

 

[Stifler's Mom]

Tell me if this sounds possible????

Trying to get the RJ up to 410, the pilots level off to build up speed, then pull up to gain that last bit of altitude needed to reach 410. As a result, they get the airspeed too slow, and have a double flame out. (Is there a speed to maintain during climb?)

Then during the descent, attempt a restart too soon and end up burning up both engines?

The reason I asked this possibility was because some instructors at FSI in ATL were talking about this scenario. Evidently, data from this accident was run in one of the CRJ simulators, or computers that depicts the flight path versus the recorded data, and this was what they believe may have happened.

I know it's nothing official, but thought it was interesting that an RJ training department was already looking at any information they could get their hands on.

 

[Lear70]

Coil, I agree with you completely. That's why I believe this "book" discussion, although good review, to be relatively unrelated to the topic. The change in TAS with an increase of altitude has nearly NO bearing on the SAFETY of flying the aircraft at that altitude. Does it decrease with altitude? Yup, forgot about that, BECAUSE THE REDUCTION IS NEGLIGIBLE and once I learned that IN THE REAL WORLD, I eventually forgot the information, just like the equation for lift generated by an airfoil in aerodynamics class we were made to memorize or where to find the data on a NOAA chart. It just doesn't apply to real-world every day flying.

Hey Lear, I think you ought to reopen that book and actually read it this time. Diggler's profile really doesn't state his experience level, which you insulted. Oakum may or may not have as much time as you. I certainly don't, but I will venture that our understanding of this subject is far more complete and accurate than yours. Before you go out and 'perform these tests' with people in the back, you may want to read and understand why you are getting these results.

I only respond in kind after I am attacked. To wit, the hypocrisy you're showing here, insinuating that I am somehow endangering the lives of my passengers WHILE FLYING A CONSTANT M.74 CLIMB FROM 29,0 TO 33,0 because of a difference in TAS that isn't going to amount to jack sh*t in the REAL world, given YOUR flight experience as well, is ludicrous, not to mention assinine. THAT CLIMB SPEED IS OUR PUBLISHED COMPANY PROFILE!

.70 at FL410 on a standard day will give you an IAS close to 200 kts. Waaay too slow for me to feel comfortable, especially with no remaining thrust. I am making no remarks about the accident, only pointing out the fact that at least one highly experienced captain seems to feel comfortable at these speeds. FL410 is probably not the place to be learning about it.

There's another reason you're not the Captain. I'm certain there are many other Captains out there who feel perfectly comfortable flying this airplane around all day at 200 Kts clean. As long as there is an adequate margin between the stall speed and the IAS, I'll fly around all day at that given IAS.

Ignorance is one thing, but insulting others due to that ignorance is another. Don't throw stones if you live in a glass house.

I could say the same for you. Once you've accumulated PIC time in just about every Lear out there (an aircraft that DOES fly at the edge of the envelope up at coffin corner), the 727, and then the CRJ, why don't you come back and have this discussion. Until then, why don't you read some more books in that glass house of YOURS.

 

[Gatorman]

I'll bet BBQ on this...

Food for thought from a previous incident.... Date: 20 MAR 1994
Time: 00:36 CST
Type: Canadair CL-601-3A Challenger
Operator: Crystal Aviation
Registration: N88HA
Msn / C/n: 5072
Crew: 0 fatalities / 2 on board
Passengers: 0 fatalities / 0 on board
Total: 0 fatalities / 2 on board
Airplane damage: Written off
Location: Bassett-Rock, NE (USA)
Departure airport: Burlington International Airport, VT (BTV)
Destination airport: Long Beach Municipal Airport, CA (LGB)
Narrative:
Both engines lost power at FL410; forced landing in a field, striking an irrigation structure and trees. Improper refueling by FBO personnel at Lawrence, MA caused the Challenger to depart with water contaminted fuel.

Yes the alt limits are dictated by the pressurization issue. where the engines are mounted on the fuselage, if they were to have a turbine rotor burst, the projectiles may penetrate the pressure dome.

I am willing to bet BBQ that when they get to the teardown report on the engines they will find water in the fuel filters. There is no other reason why BOTH engines would shut down like that. There is still enough oxygen at 410 that they did not starve because of that.

Speaking of which....when was the last time YOU checked your water drains?

 

[Capn Butthead]

I have taken the CRJ to 410 a few times (light and cold outside). It will do it if you climb the aircraft at the right speed. In fact at comair most of our climb charts show to get to 410 you have to climb out at .77 to get to 410. If you have speed you can make it no problem. Trying to go to 410 straight out of the gate is almost impossibe (as with most airliners). To get to 410 I would level off at 330 or 370 and get my speed to .79 to .82 and then climb to 410. ATC will often let you go wrong way at 390 for a while to build speed. At 410 the difference between the low and high speed cues (checkerboards) is quite large. You are not really in the "coffin corner" at 410 as long as you climb at the right speed.


As for why would you go to 410 there are a couple reasons. The fuel flow is about 500 lbs less per engine than at 33000. The air is usually smoother. And you can get good shortcuts (nice on last legs home). There is really not to much of a TAS speed difference between 330 and 410. Also if you descend right (stay high as long as you can ) you can save a lot of gas (which is nice considering most airlines are trying to stiff us on the gas). I am not saying the RJ is always going to make 410 or even that is practical. But sometimes it is practical and all you have to do is follow a safe profile.

Also, please dont assume to much with the pinnacle crash. Let the ntsb do the research. These two guys probally had a tough fight with the airplane and did all they can do. God Bless them and thier families.