CRJ200 Questions

[PGT]

For one of my classes we had to purchase the Aerosim CRJ200 software and we're going through it now, I do have a few questions.

ROLL mode is automatically active when any other lateral mode is turned off, it levels the wings if the bank is less than 5 degrees so does that mean if the bank is more than 5 degrees it will automatically hold that angle of bank?

When is 1/2 bank used? The software just mentions it limits the AP to 15 degrees.

Why does the switchover to mach/ 1/2 bank occur at 31,600 feet?

[CamYZ125]

Originally Posted by PGT

For one of my classes we had to purchase the Aerosim CRJ200 software and we're going through it now, I do have a few questions.

ROLL mode is automatically active when any other lateral mode is turned off, it levels the wings if the bank is less than 5 degrees so does that mean if the bank is more than 5 degrees it will automatically hold that angle of bank?

Yes.

When is 1/2 bank used? The software just mentions it limits the AP to 15 degrees.

We use it for single engine ops on departure (V1 cuts). Select half bank after the loss of the engine while climbing to acceleration altitude. Once at acceleration altitude and a safe speed is reached for further climb, half bank mode is de-selected. As far as I can remember, that's the only situation where we select it.

Why does the switchover to mach/ 1/2 bank occur at 31,600 feet?

Because that's when Bombardier designed it to switch? Haha... no idea.

[kellwolf]

I've used 1/2 bank in one other situation. We were accelerating from V2 +10 to 200 kts climbing out of TUL and it was moderate to severe turbulence. I just hit 1/2 bank to give us a little bit of a cushion since we were turning 180 degrees. Not sure if it made a difference or not, but it made me feel better.

As for everything else, ditto what CamYZ125 said.

[ZapBrannigan]

Any time you are below maneuvering speed for the flap configuration you are in half bank should be used -- not just in the CRJ, but in any airplane.

[kellwolf]

Originally Posted by ZapBrannigan

Any time you are below maneuvering speed for the flap configuration you are in half bank should be used -- not just in the CRJ, but in any airplane.

Agreed. I use the Vref for the flaps +10. Generally, I just try not to go below that speed unless something major is going on.

[BobDDuck]

Originally Posted by ZapBrannigan

Any time you are below maneuvering speed for the flap configuration you are in half bank should be used -- not just in the CRJ, but in any airplane.

Except during an emergency (ie engine out), why would you ever operate below a given flap maneuvering speed?

[stratoduck]

At altitude, it is possible to get an accelerated Mach stall. Loading up the wings will intensify the shock wave and increase seperation. A Mach buffet is easily obtained with older wing designs when running up against the Mach limit and a standard bank is used. It may also be felt in abrupt positive G manouvers such as a level off from a steep descent or a TCAS initiated pull up.

Just as weight may restrict access to the higher altitudes, momentarily increasing the weight with G loading may also limit the wings ability to maintain altitude at the higher flight levels.

This applies not only aircraft that are cruising in excess of critical Mach, but even more so to aircraft that are designed to always be operated below critical Mach. A strong G loading may form a shock wave on a wing that has highly undesirable effects when this occurs.

These problems have been mostly eliminated with modern airfoils.

It is unfortunate how low speed awareness if often over stressed while the dangers of high speed upset awareness are completely ignored.

[ZapBrannigan]

Originally Posted by BobDDuck

Except during an emergency (ie engine out), why would you ever operate below a given flap maneuvering speed?

Can't imagine a scenario. In the Learjet the time from Vr to Flaps 8 maneuvering speed is measured in microseconds.

[granlistillo]

I flew with a guy that routinely selected it for passenger comfort AP engaged. On an RNAV departure, I am not sure that it is a good idea, if you want to stay on the blackline...

[ZapBrannigan]

Actually, now that I think about it -- I do see people periodically maneuvering for a visual approach and banking in excess of 15 degrees when below maneuvering speed for that flap setting. (think base to final, 30 degree bank turn, at Vref +5)

Poor technique to be sure. But in fairness harder to nail down on our steam-gauges.

[Trip7]

Originally Posted by granlistillo

I flew with a guy that routinely selected it for passenger comfort AP engaged. On an RNAV departure, I am not sure that it is a good idea, if you want to stay on the blackline...

BAD BAD idea on RNAV departures

[CamYZ125]

Originally Posted by Trip7

BAD BAD idea on RNAV departures

I've never selected 1/2 bank on an RNAV departure.. does anyone know if the FMS/FD realizes half bank is selected and begins the turn earlier (in order to remain on the RNAV track), or if you just blow through the turn?

[Socal321]

Originally Posted by PGT

For one of my classes we had to purchase the Aerosim CRJ200 software and we're going through it now

sigh.......

[Polar742]

Until I flew the Big Boeing, I never ran into a scenario when a lower than standard bank angle would be used.

We'd select flaps up, then from V2+80 to v2+100, we'd use 15 degrees of bank for maneuvering. There was a weight attached to that, but we'd use the procedure every time.

The Latte Liner has an "auto" position for the bank limiter, and it takes care of all that crap for us.

[Polar742]

Originally Posted by PGT

For one of my classes we had to purchase the Aerosim CRJ200 software and we're going through it now, I do have a few questions.

That's a load of crap to be forced to purchase that.

If you can make a powerpoint presentation, you can work a FMC/FMS/MCDU- whatever you want to call it. Even better, if you have good SA, you can tell you fat fingered the entries before ATC gets in touch with you 180 miles past your destination.

hell, I'll give you one for free....

[ZapBrannigan]

I agree with Polar. Once you learn one FMS they all follow similar logic (though admittedly Universal is the Playskool FMS) and are easy to understand.

Your company will teach it to you. Your university is simply wasting your time and money.

[PGT]

FMS is easy, I got it down. The class is a requirement for my degree, $400.00 software for 40 hours of use. At least I'll be able to sell it back to my roommate so he can use it next semester.

It's interesting, we've covered fuel, hydraulics, gear, fire & protection, including a cockpit cardboard to run checklists.

[Polar742]

Originally Posted by PGT

The class is a requirement for my degree, $400.00 software for 40 hours of use. At least I'll be able to sell it back to my roommate so he can use it next semester.

That's still a load of horse crap. Whether you can resell it or not. The school should have that covered. Usually they can get that crap free to indoctrinate future customers. Law of primacy, not piracy.

It's interesting, we've covered fuel, hydraulics, gear, fire & protection,

Worthwhile to learn, especially if you dig deep into the parts to understand the basic fundamentals. Like what an IDG is, or what a variable displacement hydraulic pump is.

including a cockpit cardboard to run checklists.

A waste unless you're getting checked out in the plane. The habits should be formed with the flight programs philosophy...

IMO, of course.

[BobDDuck]

Originally Posted by Polar742

IMO, of course.

Of course

I agree though... learning systems in detail as well as the generic versions of the same system (so you can transfer it to other aircraft) is pretty useful. It will make ground school somewhere somewhat easier. However learning flows on a paper tiger is pretty silly unless you are going to go fly the plane (or sim) later on.

[SeanD]

What school is this and what is the degree?

[PGT]

Originally Posted by SeanD

What school is this and what is the degree?

pm sent

[granlistillo]

Originally Posted by Trip7

BAD BAD idea on RNAV departures

Yes, I agree it could probably bite you on the butt. When I flew with him, it was when we were getting a vector to intercept the RNAV departure, and by that time "hook" had been bypassed and it was small turns to the transition. Otherwise I would have said something.

[Speedbird172]

Originally Posted by PGT

Why does the switchover to mach/ 1/2 bank occur at 31,600 feet?

It's kinda trivial but I believe the switchover is made here because of the metric system; it is approximately 10,000 meters. Why that? Not sure, guess they just wanted an even number that was high enough to logically necessitate the use of 1/2 bank.

[N519AT]

Originally Posted by granlistillo

I flew with a guy that routinely selected it for passenger comfort AP engaged. On an RNAV departure, I am not sure that it is a good idea, if you want to stay on the blackline...

Same here. Soft Ride/Turbulence Mode and 1/2 Bank always.

[kellwolf]

Originally Posted by CamYZ125

I've never selected 1/2 bank on an RNAV departure.. does anyone know if the FMS/FD realizes half bank is selected and begins the turn earlier (in order to remain on the RNAV track), or if you just blow through the turn?

In theory, it SHOULD know you're 1/2 bank and compensate. I might try it on a normal "Intercept J29" this weekend just to verify. If you're intercepting a LOC, however, it'll clear 1/2 bank when it captures.

TURB mode, a lot of times, is sorta useless. I HAVE found that if you're in SPD mode, go through 10K and select 290 kts, if you hit TURB mode, it'll actually pitch at a NORMAL rate to accelerate rather than diving for the speed.