CRJ Series Icing Concerns and Studys

[Crossky]

I was on the ERJ-135 out of TOL and the engines were icing up. It was fun watching it shed into the engine after the crew turn on the anti-ice!

Which esteemed regional was this? I can guess.

I've seen a 1/2 inch of ice on the vert and horiz stabs after landing at ORD from over the lake. The control column was definitely 'dancing' - vibrating a little and a little less stable in pitch than usual. Like in the other posting, I've heard stories that other CRJ crews with tailplane icing accretion have lost elevator effectiveness in the flare, resulting in a firm touchdown with nose down moment and the nose wheel touching down hard immediately.

Have fun, AP off!

 

[ceo_of_the_sofa]

170/190 series EMB has no tail ice protection. Seems to be doing OK so far.

 

[BoilerUP]

Isn't the anti-ice automatic on the E145 family?

 

[JECKEL]

"I've seen plenty of ice on the vert. and horiz. stabilizers. Supposedly, it’s not that ice will accrete, it’s that it won’t exceed a point that would create a safety hazard. Anyone know what that point is?"

POAHI pretty much nailed it here.

I just happened to have sat in on a lecture/presentation by Bombardier engineers last week and the discussion was icing and the CRJ 100/200.

They claimed (and showed test flight photos) that they have intentionally accreted 3 inches of "horned shaped" ice on the leading edge of the horizontal stab and no loss of control or loss of elevator effectiveness was experienced ... so no need for heat or boots ... so their tests say. You be the judge.

 

[han_solo]

Learjets have tail anti-ice too.

 

[DoinTime]

I just happened to have sat in on a lecture/presentation by Bombardier engineers last week and the discussion was icing and the CRJ 100/200.

That same engineer will probably also tell you that "core lock" is a myth.

They claimed (and showed test flight photos) that they have intentionally accreted 3 inches of "horned shaped" ice on the leading edge of the horizontal stab and no loss of control or loss of elevator effectiveness was experienced ... so no need for heat or boots ... so their tests say. You be the judge.

I've carried around a ton of ice on the tail of the CRJ and I wouldn't ever say that "no loss of elevator effectiveness was experienced." Its not so bad that it can't be overcome with a little more pull on the yoke but it certainly isn't the same as having a clean tail.

 

[jehtplane]

The 727 also had no tail anti-icing, because Boeing said aerodynamics were such that ice didn't accumulate there.

As does the 757/767

 

[TA/RA]

I've seen the CRJ iced up pretty badly once or twice. When it looked iced up pretty bad, it handled pretty good.

I've had it get a bit unstable in the pitch attitude once, while shooting an approach in moderate icing. When the flaps went to 45, it was a handful. After getting it trimmed, it flew much better.

The people I talked to, whose credentials, knowledge, and opinion I would never question, agreed with my synopsis that keeping the CRJ as perfectly trimmed during an approach in icing conditions is a must.

Yes I know that keeping any transport category aircraft trimmed is showing proper airmanship, but this thing will bite you with little or no warning if she decides you're not treating her right.

Think of the fact that the stab-trim is moving the whole horizontal stabilizer, compared to the elevator moving a much smaller surface. When ice disrupts the airflow over the tailplane, I'd rather be moving the big piece than the small one.

 

[Salukipilot4590]

Isn't the anti-ice automatic on the E145 family?

Sure is! We've got both an auto and an all selection. The auto uses the ice detectors and will turn on when there's .5mm of ice. The all or manual will turn on the engine lips while on the ground and the leading edges (Wings and Horiz only) above 25 wheel kts. or in the air.

Its a good system overall...not much thinking required...

 

[redflyer65]

Here's the Skywest incident. They throw the pilots under the bus, but the last line says a lot as well....



http://www.ntsb.gov/ntsb/brief.asp?ev_id=20040121X00083&key=1