We don't wanna die!

[Robbo]

Not the best thing for a hostie to say in the current climate.

 

http://www.news.com.au/travel/travel-updates/flight-attendant-tells-passengers-we-dont-want-to-die-as-ice-forms-on-planes-wing/news-story/9ed3bc359c5dd5bfe6d53188b9de4cfa

 

https://www.youtube.com/watch?v=XFcTz3Jjafw

 

 

[Marty_d]

Ryanair... they probably charged 2 euro for making the announcement too.

 

 

[Oscar]

Coming back to Canberra one winter's eve from Albury in a small commuter kite (possibly a Queen Air) when the big Pilot's strike was on and Ansett had fired every pilot... sitting first row, rh side, so I could see most of what the pilot did, and I'll stake quids that he was an ex-Ansett Captain. No FO, of course, on something that small.

 

Over Tumut, we were in the middle of HUGE cumulus towers, lightning going off all around. Then I note the PIC reach down and pick up a torch, and look out the left hand side, shining the torch outside.. WTF?? Then he ( nonchalantly) did the same sweep of the rh wing and spinner - there was easy three inches of ice on the L/E and about the same on the nose of the spinner.

 

AHA - says I - we're going to die. On the upside: at least it'll be quick, and there are no fat American matrons shrieking 'OH MY GOD' aboard, as one cannot get up and hit them ( see also: 'Flying High').

 

Descent into Canberra, heavy rain... well, at least it isn't hail, so we should shed the ice. We WILL survive! Runway lights appear - tracking well over 30 degrees off the starboard bow, Captain.... and the thing is being blown around like a balloon in a hurricane. AHA, says I - at least we'll die where we can be found!

 

Main strip, down the centreline, pointing at the terminal.... then with about 2 feet height to spare, the PIC kicked it straight and deposited us on the tarmac without even a bounce. Taxied in; the Airline staff didn't bother bringing out umbrellas, the rain was torrential and horizontal. I was the last pax out; the pilot was handing out the luggage from the nose, soaked to his jockstrap. There was STILL bloody ice dripping off the wings! Ambient was about 2C, if that.

 

I said to him: "Thanks, that was a bloody wonderful landing in these conditions, and don't these have de-icers?"

 

"Thank you, sir, and yes, they are SUPPOSED to'' - in a voice that suggested somebody in Maintenance was going to be drilled, reamed, punched and bored with exceptional malice.

 

 

[Pearo]

[Robbo]

I still get chills (pardon the pun) when I hear the word icing...

 

 

[BLA82]

That is a scary recording

 

 

[silvercity]

And she decided to continue to her destination!! You've got to be kidding. I would have landed at that airport five miles away ... and gone straight to the gents!

 

 

[Guest ozzie]

Seaview Airlines Turbo Commander, flight into known icing in aircraft not equipped lead to loss of aircraft will 9 pax. Oct 1994.

 

A couple of MU2's were lost here due to ice building up on the rear underside of airframe leading to exceeding aft CG limits and loss of control.

 

 

[facthunter]

You generally can keep an airliner free of ice, if you operate it correctly. At altitude the air is dry and the particles are ice crystals (EXCEPT near and in those Cumulo Nimbus whoppers) and the speed they cruise at warms the air 33 degrees and you can bleed a lot of hot air off the engines, to warm your wings, BUT at the height WE fly, anytime the OAT is below freezing you can accumulate airframe ice quite quickly. It will destroy lift, affect controllability and add weight and it can be quite rapid. If it happens keep your speed up, as your stall speed is higher, descend to warmer air and get clear of rain. You shouldn't be in cloud but ice will form there anytime the temp is right for it. If the temp is below freezing and you fly through one small cloud the windshield will have ice on it. Nev

 

 

[Old Koreelah]

You generally can keep an airliner free of ice, if you operate it correctly. At altitude the air is dry and the particles are ice crystals...and the speed they cruise at warms the air 33 degrees ...

Can you expand on this bit Nev; do you mean that air friction heats the aircraft skin 33 degrees?

 

 

[Kyle Communications]

Well the MU2 is well known as "the widowmaker"

 

 

[facthunter]

yes OK. That is the situation. Quite remarkable isn't it? It depends on the speed you are cruising at. That's about right for Mach .82 at FL330. Nev

 

 

[dutchroll]

Air friction and compressibility at jet cruise speeds does indeed warm the skin considerably, although this may or may not be conducive to icing depending on the circumstances.

 

The definition of "icing conditions" is pretty universal in the big jet world because it's simply defined by physics. Specifically, most operations manuals state the following (or equivalent words):

 

"Icing conditions exist when visible moisture is present (clouds, fog, rain, etc) and the TAT is at or below 10 deg C, except during climb and cruise where SAT is below -40 deg C"

 

On the ground, simply substitute "outside temperature" for TAT. In other words, if your aircraft skin temperature is less than 10 deg C you are susceptible to ice formation. However actual outside temperatures below -40 deg C are considered too cold to be conducive to ice formation on the aircraft surface.

 

TAT = Total Air Temperature = temperature measured by the temperature probe on the aircraft surface. The faster you go, the higher this is because the air in the probe gets a "ram rise" (proportional to the square of your Mach number). This number is significant to pilots because it is equivalent to the actual temperature of the aircraft skin.

 

SAT = Static Air Temperature = temperature of the air measured by the probe if the probe wasn't moving (essentially should be equal or close to the actual outside air temperature).

 

Ain't no planes on this forum which will have to worry about TAT, nor which will avoid icing conditions by going where the SAT is < -40 deg C!

 

 

[Aldo]

If I remember correctly the Concord had an automatic slow down function (or warning) if the nose temperature exceeded 121 deg C cruising at Mach 2 with th OAT at 62,000 feet being about -56c. The fuselage would expand due to heat by several inches during flight, amazing what a few molecules will do if you run into them fast enough.

 

Dutch may be able to expand on the above if my number recollection is incorrect.

 

Aldo

 

 

[dutchroll]

-56 deg C is correct for 62,000 ft in an ICAO standard atmosphere.

 

The relationship between TAT, SAT and Mach Number is:

 

TAT = SAT x (1 + 0.2M^2)

 

The formula assumes temp measurements in degrees Kelvin, so the conversion is:

 

-56 C + 273 = 217 deg K

 

TAT = 217 x (1 + 0.2x4) = 217 x 1.8 = 390.6 deg K

 

Converting from degrees Kelvin back to C

 

390.6 - 273 = 117.6 deg C

 

So given the TAT should be about 117 deg C, you would expect the skin surface temperature to also be about 117 deg C as the aircraft skin is affected by the same compressibility and friction as the temperature probe.

 

 

[Guest SrPilot]

Ain't no planes on this forum which will have to worry about TAT, nor which will avoid icing conditions by going where the SAT is < -40 deg C!

Thank goodness! I had just read dutchroll's formulas and explanation of TAT, SAT and Mach Number and was dumbfounded. How in the world can I ever understand this stuff? Not an engineer, mathematician, or weather person. Just converted from commercial to sport pilot, still operating in F (not C or K), can't spell TAT or SAT . . . . What am I to do?!! Then he tells me the bottom line - don't worry 'bout it; you'll never need this in your A22LS.

 

Man am I relieved. I can stop converting and go flying. Well, except that we have forecasts for tomorrow involving possible thunderstorms changing to snow showers later in the day. Ah, southern U.S. winters. We have a formula for them, but it doesn't solve . . . .

 

 

[Robbo]

Welcome to ATPL exams....

 

 

[Guest SrPilot]

Welcome to ATPL exams....

Thanks Robbo. Can't spell that one either.

 

 

[Robbo]

Thanks Robbo. Can't spell that one either.

Airline Transport Pilots Licence

 

 

[Guest SrPilot]

Airline Transport Pilots Licence

Thanks Robbo. I knew that . . . but we spell "licence" "license" so I guess I was telling the truth in a way. I cannot spell it ("correctly").

 

 

[Robbo]

Thanks Robbo. I knew that . . . but we spell "licence" "license" so I guess I was telling the truth in a way. I cannot spell it ("correctly").

Ahhhh I got that one spelt correctly, thought you would know it but thought I would say it anyway.

 

 

[facthunter]

It.... It is easy. Nev

 

 

[dutchroll]

Oh don't get me started on the American spelling of "aluminum" (which doesn't conform to the standard spelling principles of elements in the Periodic Table). Just gotta be different, don't ya'?

 

 

[facthunter]

Nucular instead of nuclear. Nev

 

 

[Robbo]