Jet aircraft: Trouble in Icing- What can you do?

[PA31Ho]

so would you delcare an ice emergency or something so you can go >250 at 6K'?

 

[Junkflyer]

The 747 does have leading anti-ice unless the flaps are out.

 

[SabreFlyR]

In response to the silly and senseless ridicule this guy got (http://forums.flightinfo.com/showthread.php?t=71599) for actually using this forum for something meaningful and educational, I thought I would follow his lead and do the same. If you don't like it, tough $hit!

1) So, you are stuck down at 6,000ft 40 miles from your intended airport of landing, picking up moderate icing at a pretty good rate and needing to land. No VMC within the range of your fuel or warmer WX to climb into, so you are going to have to fly around in the ice. Well, your wing anti-ice (Bleed Air) just signed off on both engines. It's gone for good. For whatever reason, a freak of nature failed the valves shut. How can you heat up those wings enough to keep the ice off? Be specific about what you can use, and how to use it to determine that you are not picking up any ice and shedding whatever ice you had on your wings. (Clue: In doing this, you'll shed ice from the entire airframe, not just the wings)

Any old Sabre pilot should know this. Go fast and land with part flaps.

 

[HawkerF/O]

You might doublecheck your C500 manual...If I recall correctly, -30 is the magic number there.

If that is the # you got, the you got some bad information. I assure you that it is -40C SAT.

Now, let's say it's -10C at 4000 feet...you need 20 degrees of ram rise to get to +10C. That requires a TAS of 390 kts, which, due to the colder than standard temperature, is a 400 knot INDICATED airspeed. I've never flown anything that allows more than 370 down there...ruh-roh, Raggy!

What's your point? If you can't do it, you can't do it. I never said this method was a guarentee, but it is pretty close. Most of the time it will work for you if you have the power and speed. And if I recall, a Falcon 20F gets pretty close to 400KIAS all the way down. If it is not 400, it's within 10 Knots.

The guys I used to fly with who also flew Sabreliners said you just push it up to 300KIAS, and all the ice goes away...they never told me how to shoot an approach at that speed, though

Those guys are lucky the temp was never colder than it was, or they would have learned quite a lesson. As for the approach (ILS), take it as fast as you can to the marker (hand fly it, the A/P won't keep up), then power to Idle, speedbrakes to flap/gear speed, retract speedbrakes, configure fully, hello Rabbit. You should be stable at about 1 mile out. At that point, you are pretty much comitted to landing.

 

[HawkerF/O]

so would you delcare an ice emergency or something so you can go >250 at 6K'?

just an emergency. Hopefully you are away from any high volume airports.

 

[NoPax]

This has been an interesting discussion. FN FAL's link is an interesting read...glad I was also on the right track (the ice would have begun melting on my way to M1.0!)

 

[Amish RakeFight]

Exactly! -40 SAT is the magic #. As for being down low, you are right, no manufacture has ever seen ice on the airframe at +11 or higher, so accelerate until the TAT reaches +10 or higher and you can fly around all day long and use the TAT as your Anti-Ice. Just keep it above +10 and you'll never get a hint of ice on the entire airframe and it will shed what Ice you have already accumulated.

SAT = Standard Atmospheric Temperature

TAT = ???

 

[PA31Ho]

total air temperature.. basically the greater friction caused by an increase in airflow over the wing

 

[MauleSkinner]

SAT = Standard Atmospheric Temperature

Saturated Air Temperature...basically free-air temperature.

TAT = ???

Total Air Temperature...includes ram rise due to friction and compressibility.

Fly safe!

David

 

[Gulfstream 200]

Standard?
Saturated?

hummm...

how about Static? (not that it matters..)

:0