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

 

[Rez O. Lewshun]

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

Too bad no one was able to speak on thier behalf....

 

[kmox29]

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

CAREFUL DoinTime...that one sentence can turn this thread into a 15-pager with the last 5 pages being Mesaba vs. Pinnacle

 

[BrickTop]

Good responses still in context with original thread!

 

[DrewBlows]

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.

Perhaps I have to bone up on my CRJ systems, but how could the control column "dance" because of icing conditions?

To the best of my knowledge the CRJ flight controls are hydraulically actuated. The control column is connected to the actuators through steal cables. The cables move a hydraulic switch which directs the flow of hydraulic fluid it the appropriate direction until the control surface is in the directed position. This is a one way system. The control surface cannot redirect the hydraulic fluid and move the switch attached to the cables thus cannot move the control column.

The force you feel in the control column is artificial. It was put in place so pilots would fly the airplane 'in trim,' so we wouldn't over-stress the airplane, and because we as pilots like to feel like there is something on the other end of the controls. If anyone has ever flown a simulator with broken force feedback you understand how frustrating (and dangerous) it would be to NOT have a feel for the airplane trim condition.

My point is, I think accounts of 'loss of control effectiveness' are exaggerated. Or perhaps it would be more accurate to say loss of the feel of control effectiveness is exaggerated. I suppose it's possible to tell your controls aren't effective if you pull back to rotate and the airplane continues barreling down the runway, or you pull to flare and the airplane continues to descend.

I have no doubt the Challenger derived airplanes have an icing issue, but I don't think loss of feel (or feeling 'flutter') is one of them.

 

[JettBoii]

We have on more than one occasion had ice build up on the windshield wipers only to find that there was ice on the leading edge of both wings with NO ice light! After immediately turning on the wing/cowl anti-ice we both watched as it flaked off! It was written up both times; I am sure it was "ops checked good". If your in icing comdition as the POH states then turn in on; don't wait for the ice light. After all as the famous SS said in training its free, works well and lasts a long time. If you lose the power then level off and wait until you have the energy to do so.

 

[Poahi]

The stab trim is electric. I've flown an ILS with zero hydraulic pressure. It wasn't pretty, but we all walked away from the sim.

The key to me is to watch the green line. If it is above your vref, there is a good chance you've got ice.

 

[TA/RA]

Drew, don't ever compare a sim with the "force-feedback" turned off with an airplane. That is the most asinine thing I've heard in awhile. When all the systems are powered up the yoke and rudder pedals will deflect with the control surfaces. Otherwise we would probably be flying with the game controller from a Playstation 2. The next time you are in the airplane on the ramp with a strong wind blowing, if the rudder is deflected, the rudder pedals will be too, if all of the systems are powered up. Yes, the control feel is artificial, but it's there. Also, if you deflect the control surfaces with the trim switches, the yokes will move with them also. But in this case, I'm not sure if the chicken or the egg came first.

 

[chignutsak]

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?

3.54762385 inches

 

[Rez O. Lewshun]

The key to me is to watch the green line. If it is above your vref, there is a good chance you've got ice.

Not sure I'd trust green line with ice accumulation...

 

[CFIT]

Too bad no one was able to speak on thier behalf....

Actually there were a number of people that were made available on behalf of the pilots. I know both in question very well and both have told me that they felt they were treated and given ample support by the company.

The Captain in question is a very good friend of mine and is a strong anti-ALPA advocate. The first officer at the time is now a Captain and although was on the OC has told me the company and others were very supportive of the incident.

As I recall the captain had his LCA authority removed for 6 months by the FAA.