High altitude flying and Risk

[IFLY_INDIGO]

Flying at usual cruising flight levels is good for airline. It saves money.
But it is certainly not good in terms of aerodynamics. It causes severe control issues. Many crashes can be attributed to it.

How many times do we think about it in routine flights while craving/fighting for higher FLs?

Your thoughts..

[Capt Claret]

It causes severe control issues. Many crashes can be attributed to it.

Severe control issues. Many crashes.

Really?

[DaveReidUK]

Very few crashes happen at high altitudes. :O

[vilas]

Want to travel by road?

[Dont Hang Up]

Your thoughts...

...my thought?

Your premise is ill informed.

[Mad (Flt) Scientist]

...craving/fighting for higher FLs

If anyone were actually doing this it might have a risk.

if people (as they actually do) plan their flights accounting for the performance capabilities of their aircraft, with all the requisite margins, it's no more hazardous at high altitude than at medium (and arguably SAFER than at low)

[aterpster]

This is an absurd thread.

[oceancrosser]

As the mother said to the student pilot: "Be careful and fly low and slow".

This is one thread for jetblast.

[albatross]

Full quote is "Fly low and slow and throttle back in the turns!" I think.

[Dan Winterland]

Very few crashes happen at high altitudes

And very few people die flying. What tends to kill them is not flying all of a sudden!

[A Squared]

But it is certainly not good in terms of aerodynamics. It causes severe control issues. Many crashes can be attributed to it.


Can you name 3 airline crashes attributed to "severe control issues" resulting from high altitudes? I can't. Perhaps they could be considered a factor in AF447 or Air Algerie 5017, but hem maybe not, either. There were a whole bunch of things going wrong with both those flights. All the high altitude loss of control accidents I can think of had something else cause the loss of control.

So I'm coming up short with Airline crashes which can be attributed solely or primarily to "severe control issues" at high altitude.

[vilas]

IFLY_INDIGO really?
Some of your questions create the doubt.

[aterpster]

Dan Winterland:

And very few people die flying. What tends to kill them is not flying all of a sudden!

I can think of a few exceptions off the top of my head:

MH17 and TWA/UAL over the Grand Canyon and over New York City.

[IFLY_INDIGO]

Before posting a negative answer/remark, please ask yourself "how many minutes in your flying career, you have hand flown a commercial jet at high altitudes?". Try maneuvering the airplane in simulator at high altitudes and judge your comfort level yourself. See the airplane reaction.

Its very easy to show your macho in the posts here. My question is for the pilots who accept that 'danger is real' and keep it on their mind

[A Squared]

I'm still waiting for your list of accidents which have been attributed to "severe control issues" from high altitude flight.

[wiggy]

Try maneuvering the airplane in simulator at high altitudes and judge your comfort level yourself. See the airplane reaction.

Never mind the simulator. Before the days of RVSM it was not uncommon to hand fly airliners (even heavies like the 747) for periods of time at high level, e.g for trimming purposes or just for the sake of it. At no time do I remember reports of there being severe control problems or severe control issues.

Its very easy to show your macho in the posts here.

I'm all for not cruising right on Max level for the sake of it but as in all things there's a balance. Some would regard it as being "macho" if you decided to stay low to penetrate monsoon weather, rather than being up at a sensible FMC related cruise level.

[Intruder]

Before posting a negative answer/remark, please ask yourself "how many minutes in your flying career, you have hand flown a commercial jet at high altitudes?". Try maneuvering the airplane in simulator at high altitudes and judge your comfort level yourself. See the airplane reaction.
Commercial airliner? A few hours. RVSM has made that practice illegal for the most part.

Tactical jets (A-4 and A-6), which are MUCH less stable than a commercial airliner? HUNDREDS of hours! The A-4s I flew seldom had working yaw dampers, much autopilots. Virtually ALL was hand-flown. The A-6 had a better autopilot; but still failed quite often, compared with the 747.

Still, in over 13,000 hours over 40+ years of flying, I have yet to see a "severe control issue" or ANY crash due to high-altitude flight.

We're still waiting for your examples of "severe control issues" and crashes attributed to "Flying at usual cruising flight levels"...

[vilas]

Try maneuvering the airplane in simulator at high altitudes and judge your comfort level yourself. See the airplane reaction
You seem to be traumatised by your sim experience. Every batch during type rating is given handling at FL350 and shown that even at bank angles of over 30 degrees there is substantial margin between MMO and Valpha prot/ Vls. I am sure it was a sim problem. The accidents that happened were because the pilots yanked the stick back in alternate law. Had they done nothing it would have been safe. If you compare CFIT accidents you may change your opinion.

[gatbusdriver]

I agree whole heartedly, hand flying at altitude is extremely dangerous if you are close to your max FL and yank the stick back as your are dumped into unreliable airspeed, it could definitely result in death!

Of course you could breath for 1 second, work out what has just happened and why, whilst you are in no real out of trim condition and then apply the necessary memory items.......oh there we go........disaster avoided.

Whilst we (I) talk about unreliable airspeed, has anyone tried 4 degrees and 70% in cruise on the B777 in the sim? Not convinced I would try that myself, more like 2 degrees and 85% (depending on weight etc).

Anyway......jetblast here we come.

GBD

[galaxy flyer]

Intruder,

Dropped off the tanker in the mighty Hun one night with lots of fuel. Lead asks for a block to 430. Controller approves and watches us fall out if the sky in the low forties, one by one each plane reached its exact coffin corner. Fun times, especially the descent waiting waiting for enough margin to pull a bit.

Years later, during Desert Storm, hand flew the C-5 across the Atlantic and once back up the Med from the sandbox.

OP,

If you are fearful of operating a jet within the prescribed envelope, may I suggest a career change.

GF

[PEI_3721]

A better question for the 'questions' forum would be to ask where the originator's belief came from.
?

[wiggy]

Whilst we (I) talk about unreliable airspeed, has anyone tried 4 degrees and 70% in cruise on the B777 in the sim?

Yep, fun isn't it..

....Like you I always used to think in terms of have 85-90 and 2 degrees as starters and I have to be honest and say even now I might still shoot for those numbers intially if I had just lost airspeed and knew for sure I had just been in S&L flight.

You may be aware of this, if so apologies for boring you, but I gather the Boeing logic for their "new" numbers is if you don't know your starting point ( as in were you S&L or not when you lost data? ) 4/70 will keep you inside the envelope long enough to get the ECL actioned, but there's obviously no guarantee at all that you are going to immediately be in level flight ....

[Intruder]

Dropped off the tanker in the mighty Hun one night with lots of fuel. Lead asks for a block to 430. Controller approves and watches us fall out if the sky in the low forties, one by one each plane reached its exact coffin corner. Fun times, especially the descent waiting waiting for enough margin to pull a bit.
Yes, but you neither had "severe control issues" nor any crashes, even at the edge of the envelope!

Once I had to refuel from a KC-10 in the 30s (only hole in the clouds) while in a loaded A-6 with a buddy store. We had 3 A-6s and 4 A-7s in the flight. The A-7s couldn't get in the basket at all due to the speed of the heavy KC-10 and the wake turbulence. I could only get in with a running start once we were a bit lighter, and keep Mil power until I finally dropped out. I then transferred fuel to the A-7s and repeated.

[Dont Hang Up]

The premise of this thread is that the fundamental basis of modern commercial aviation, largely working around jet aircraft operating at high-altitude, is unsafe.

As most available statistics would suggest the opposite, I suggest the original poster needs to better justify their position before the proposition can be taken seriously.

[aterpster]

Dont Hang Up:

As most available statistics would suggest the opposite, I suggest the original poster needs to better justify their position before the proposition can be taken seriously.
He can't and he won't.

[Una Due Tfc]

A colleague of mine was telling me he had a flight of one of the US majors request descent from FL390 due to receiving a warning about high Ozone levels in their vicinity. I must confess I have never received training regarding Ozone and it's possible effects on pilots.

[wiggy]

Academic paper here ( see para 3.4)

http://iopscience.iop.org/article/10.1088/1748-9326/8/1/014006

No company training or procedures where I work either.

[gatbusdriver]

Makes sense wiggy,

Cheers