Darn it's quiet? Any idea why?

[JetCapt69]

why?

The chance of both systems becoming blocked at the same time is slim to none, even if they did not have adequate Prist in the fuel. I don't think you're even close with this theory. As I said, though, I will refrain from speculating publicly. BTW, they were IMC.

The NTSB preliminary report:

http://www2.ntsb.gov/ntsb/brief.asp?ev_id=20040804X01143&key=1

Like I said, it was only speculation with no internal knowledge. I find it curious that you refrain from speculating. You seem to have some inside information or is it just rumor?

I know of some aircraft (Cessna series) that the AFM recommends putting the ignitors on for descents intiated above FL350 if a rapid reduction of power is initiated.

Guess we will find out in about 9 months or so.

 

[FlyChicaga]

Interesting. Since we are all speculating, from my rather inexperienced perspective it may sound as though someone forgot the engine anti-ice after entering IMC.

 

[FracCapt]

Like I said, it was only speculation with no internal knowledge. I find it curious that you refrain from speculating. You seem to have some inside information or is it just rumor?

No inside information. If I felt I had concrete evidence rather than just speculation, I would state what I think. Since I don't know for sure, I won't say publicly. What I think is definitely not rumor - I haven't heard any rumors about this incident other than what has happened to the crew(both PIC's, supposedly demoted to SIC's)...it's strictly my opinion based on knowledge of the aircraft and general practices in turbojet aircraft.

 

[FracCapt]

Interesting. Since we are all speculating, from my rather inexperienced perspective it may sound as though someone forgot the engine anti-ice after entering IMC.

I must admit, that thought crossed my mind at first when I heard they were IMC...but since the engines were flamed out by FL350(possibly higher), the temp would likely be too cold for ice to form, unless involved in some type of convective activity. Generally, engine anti-ice is used from +5C to -15-20C, depending on the specific aircraft. RAT/TAT would likely have been -30C at the warmest up there, with SAT being -40C or colder.

 

[FlyChicaga]

I must admit, that thought crossed my mind at first when I heard they were IMC...but since the engines were flamed out by FL350(possibly higher), the temp would likely be too cold for ice to form, unless involved in some type of convective activity. Generally, engine anti-ice is used from +5C to -15-20C, depending on the specific aircraft. RAT/TAT would likely have been -30C at the warmest up there, with SAT being -40C or colder.

Very true. I was just thinking convective activity since they were a) IMC and b) near Florida/Gulf Coast. Would lead me to believe there were buildups in that area, reaching their altitude. Of course, if that were the case, then there is a whole other mess here, about flying into a possible CB.

I guess we'll just have to wait and see when the facts come in.

 

[English]

There is a common misconception that in the higher altitudes, it's too cold for icing.


Not so.



Go read the NTSB safety recommendation A-04-34.

There was an MD-82 on June 2, 2002, at FL330, that experienced a loss of power on both engines due to high altitude ice crystals adhering to the engine inlet pressure probes. Just like on the Air Florida crash, but at 33,000 feet. They were IMC (visible moisture, less than 6 degrees C) and did not use engine anti-ice. On descent they were able to restart at 17,000.

 

[PHX767]

Well, at FL410 it is just going to be ice crystals, not conducive to icing.

A big BANG when the power is pulled back, sounds like a compressor stall. I've had a number of minor compressor stalls in different planes, and the higher the altitude the easier it is to get one. I've not experienced one in the Beechjet, but then I pull the power back reaaalllly slowly when at high altitude. The combination of axial and centrifigual (sp?) compressors seems fairly resilient.

The fuel contamination theory is lame. The Beechjet feeds the fuselage tank directly to the mains automatically. Any contamination would be diluted. And both engines at the same time? Very hard to nail down. Will have to look at the crew testimony.

 

[FracCapt]

There is a common misconception that in the higher altitudes, it's too cold for icing.


Not so.

They were IMC (visible moisture, less than 6 degrees C) and did not use engine anti-ice. On descent they were able to restart at 17,000.

Anybody that associates strictly altitude with potential to pick up ice is an idiot. Notice I stated that above FL350 it was likely -30C or colder? I have NEVER seen it warmer than -20TAT at that altitude. I never said that it was too cold based on the altitude....I said it was likely too cold based on....THE TEMPERATURE! What a novel concept.

If you're IMC and the temp is -6C, and you DON'T have anti ice on....you're an idiot.

 

[banned username 2]

Anybody that associates strictly altitude with potential to pick up ice is an idiot. Notice I stated that above FL350 it was likely -30C or colder? I have NEVER seen it warmer than -20TAT at that altitude. I never said that it was too cold based on the altitude....I said it was likely too cold based on....THE TEMPERATURE! What a novel concept.

If you're IMC and the temp is -6C, and you DON'T have anti ice on....you're an idiot.

I have been rained on at FL350... very bizaar weather day... was about 10 years ago...

 

[Jetsi]

Ice Ice Baby

Hey Guys and Gals,

The ice theory would make the most sense. And before you say it can't happen, let me get my 2 cents worth.

I was at 410 going from DAL to CHS on my Captain upgrade ride. Cruising at .76 in IMC dodging storms over AL, RAT -42 SAT -60, we iced up all the pitot tubes and static ports, leaving me with an attitude indicator and a questionable AOA gauge. Got everything back descending through 8,000 feet. It has happened to at least 3 other crews that I know of.

All of the anti-ice was turned on, including the engine heat.

Lovin life,

Jetsi