Inappropriate comments about RJ crash?

[avrodriverj85]

Letter to the Industry

I read this from the website "ProPilot" back in 1997, I think it applies here:

[size=-1] Accidents happen in this business. They happen for a variety of reasons, but human factors (usually pilot factors) are the leading cause. When accidents happen, people die. Training and experience are two of our best defenses against these accidents. You owe it to yourself, your crew, your passengers, your airline, your family, your friends, your fellow pilots, and your profession to be proficient and qualified. [/size]

[size=-1]I’ll bet a few of you are wound-up by now and asking the age-old question, “Yeah, but how do I get that experience?”. We’ll get to that shortly, but please don’t try to get that experience as part of an airline crew. The First Officer is NOT a trainee. The F/O is a highly qualified pro who is, by law, qualified to perform the same tasks (with minor exceptions) as the Captain on his/her checkrides. The Captain and the F/O (and F/E, if you’re lucky enough to work with one of these increasingly rare types) are a CREW. While most F/Os lack the depth of experience of the captain (especially in the particular aircraft type), they are light-years ahead of new commercial pilots in all aspects of flying ability, knowledge and experience. The crew interact as experienced operators to create a safe and efficient flight environment. This experience that they possess did not come from attending classes, nor from CRM exercises; it came from years of flying airplanes. [/size]

[size=-1]Get your experience the old-fashioned way. Go out and fly as PIC in an airplane you can handle. Learn it well. Fly other airplanes. Learn their characteristics. Become a pro (this is a state of mind -- an attitude toward your profession). Flight instruction, while not involving a lot of “stick time”, will teach you more about flying than you have learned while obtaining your commercial pilot certificate. Pipeline patrol, sightseeing, aerial photography, skydiving operations (they jump, you stay in your seat), are all good for building experience. Get on with a charter operator. Fly night freight. Fly in the military. As you transition from one type to a more complex type (at a rate you can handle), you’ll build that elusive experience (which would be better measured by years, seasons and number of flights, rather than by hours). [/size]

[size=-1]While we’re on the issue of experience, let’s cut through all the crap that you hear about type ratings. At 250 hours you’ve got as much business being in command of a Citation, Beechjet, BE1900, or B-737, as you do in command of the Space Shuttle. Yup. That’s what I said. “In Command”. That means you’re “it”. You are the final authority as to the conduct of the flight. You help to create a comfortable, well-run flight-deck. You contribute. You listen. You discuss. You direct. You teach. You learn. You fly. You support. You make decisions. You handle problems. The other pilot(s) look to you for mature, seasoned, sound judgment. Sorry, but at your level, you’re just not ready. Anyone who tries to tell you otherwise is setting you up for a big fall, or just wants your money. I realize that you can probably pass the type-rating check, but that is a snap compared to what will be required of you as a captain. After all, that is what that piece of paper entitles you to do -- act as PIC of that type aircraft, with a brand-new low-experience SIC sitting next to you, a bunch of trusting souls in the back, absolutely at-minimums weather at your destination, with an alternate that is no piece of cake either, and handle anything that might go “Murphy’s way”. Don’t be fooled into thinking you are ready for that. Instead, ask yourself why your school is offering that type-rating. Could it be to draw more students? Those simulators cost MILLIONS of dollars, dollars that could be spent on an education you need and flight experience you can use (or maybe not spent at all, with lower tuition the outcome). Tell your school to put away the expensive unusable toys. [/size]

[size=-1]Last, but certainly not least, pilots need a solid grounding in CRM. Practice CRM techniques every time you fly. Fly with other pilots. You must be able to interact in a crew environment, and the time to start learning is now. The benefits of solid CRM programs are recognized throughout the world as contributing to a safer flying environment by maximizing the crew’s synergy. I realize this is hard to do in the situation most of you find yourselves in, but do the best you can -- it will pay off in the future. Try to fly with a single-pilot operator. Even if you don’t get much actual “stick time”, you’ll gain important experience by watching and participating. Most of these pilots would be happy to help someone else, and happy to have the extra set of eyes and ears. One last thought, attend a good CRM course. [/size]

[size=-1]Now, let me set the record straight. I am not a “Grinch”, nor am I an old curmudgeon. I have seen hard times, but I’ve been incredibly blessed with some very good deals in my career. I merely see us, as an industry, irresponsibly creating some very un-realistic expectations for our next generation of pilots. [/size]

[size=-1]To My Fellow Pilots:
[/size]

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  [size=-1]Keep holding the standards high and protecting the profession. We all know that there is no easy way to succeed. Do all you can to encourage and assist these future pilots, and help them to understand that the “no easy way” method might help to save their ass someday. [/size]

[size=-1]To Airline Management:
[/size]

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  [size=-1]Give new pilots all the breaks you can. But realize that at some point PFT brings you pilots with money (or debt) and does not bring you the best group of pilots you could get. By the way, do you advocate PFT for managers, or do they need to have an established “track record”? That’s what I thought.... [/size]

[size=-1]To University Faculty and Administrators:
[/size]

• 
  
  [size=-1]Please do not allow the lure of high student volume, or the pressure put on you by the administration to cause you to lose sight of your real job. Your job is to mold, develop, guide, encourage, teach and assist some very talented young (and not so young) pilots on their path to careers as professional pilots. They must be aware that real success is not achieved overnight. They must be well-prepared for the future. “Looking good on paper” doesn’t count. You are their link to reality. You are the industry’s link to the future. [/size]

[size=-1]To Future Pilots:
[/size]

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  [size=-1]You are the future. Please push yourself. Don’t expect a quick route to the majors. You’re gonna work your butt off to be successful. Study hard. Study beyond the required courses. Learn everything you can about your profession, including its history. There’s a lot in our history we don’t want to repeat. Insist on being ”pushed” in your flight training. Set your standards extremely high. Be a pro. Settle in for the long haul -- you’re in a tough career, but one with many rewards. Enjoy the good breaks you’ll get in your career. Display integrity. Demand the best from yourself on every flight. Set a positive example. Learn, and never stop learning. Teach, and never stop teaching. Remember those who helped you in your training and in your career, and be sure to “pass it on” to others who will need your help someday. You’re coming into a great hiring boom, and opportunities will be there. Don’t ever give up. Good luck. God bless. Fly safe. [/size]

[size=-1](Signed)[/size] [size=-1]An Anonymous B747 Captain Who Cares [/size]

 

[PCL_128]

I beleive I read in an earlier post that the spoilers PARTIALLY deployed because of the loss of hydraulics associated with the dual engine flameout.

Correct. The flight and ground spoilers are powered by Hyd Systems 1 and 2 which are powered by the engine-driven pumps. When you lose both engines, you lose both EDPs and the spoilers are useless. The spoilers will "float" because of the low pressure over the wing. It's only a few degrees, but it shows up on the DFDR data. They couldn't deploy the spoilers if they wanted to.

 

[surplus1]

What type of climb mode does the CRJ A/P use? Do you climb in V/S, or A/S -Mach?

If you climb in V/S,.............. why?

enigma

Basically there are 3 options available: pitch mode, IAS/Mach hold and VS mode for an autopilot climb. The choice is SCD (subject captain's discretion). Any of them will work but two of them require more monitoring. The failure to monitor and correct as necessary can put the airplane behind the power curve in pitch mode or VS mode.

VS mode tends to be "popular" for three reasons: 1) it is more "stable" that the IAS/Mach hold mode, and 2) it complys easily with the ATC min climb rate of 500 fpm. 3) you don't have to make any changes (assuming you set it right to begin with.

In going to FL410 there are also 3 options as related to climb rate (VS). You can chose to do it at 500 fpm, 300 fpm or 100 fpm, all 3 of which are "charted" rates of climb for that FL. Weight and ISA value should tell you which is more practical on a given flight. THe choice of the 2 lower rates would require you to advise ATC, which is why the 500 fpm rate is normally chosen. All three of the rates presume a minimum climb speed of 250 KIAS or Mach .70.

If the airplane can't maintain a 500 fpm VS at those speeds it is telling you that the selected altitude is outside the envelope on this day/time. You can then chose 300 fpm or even 100 fpm if you're determined to go to that FL. Of course, all of this assumes that you understand what is happening and why.

At any point where the airplane can't maintain 250/.70 airspeed during the climb, something has to give. It's up to you to decide what that will be.

If for whatever reason you allow the AS to decay below that point (250/.70) while you continue the climb, it's a foregone conclusion that 1) you are already using all available power to climb, and 2) there will be no excess power available with which to accelarate once you get to the target FL. The AOA and resultant drag is just too high for acceleration because there is no excess thrust available. (That was the case with the accident aircraft).

It doesn't really matter whether the flight level is 410 or some lower level, e.g., 370 or 350 or even 310. It's a function of thrust available vs weight and ISA value. The "principle" involved remains the same. In other words there are days when this airplane can't operate successfully at FL410 and days when it can't operate successfully at FL350. If the crew doesn't understand these relationships and why they exist, the recipie for trouble and potential upset will exist. There is nothing "killer" about FL410 per se. In this case, it is quite possible that the aircraft may have been able to operate safely at FL410, (I don't have charts in front of me) but the method the pilots chose to get there made that impossible.

Power available vs power required is a factor in all airplanes, whether or not they happen to be "jets". Whenever the power required exceeds the power available, the pilot has to do something to change that equation or eventually the airplane will stop flying, and an "aerodynamic stall" will ensue. This can happen at any altitude. Is it more likely to occur at higher FL's? Yes it is, but in reality the wing doesn't know what the flight level is. It just knows that in a given atmosphere at a given temperature, a given amount of power is required to maintain level flight. At a given AOA, airflow separation and a stall will result regardless of speed. Excss power is what makes it possible to achieve the desired speed or maintain the minimum speed at a given weight, altitude, temp.

Recovery from that "stall" will always require a reduction in the AOA and more power. Whenever additional power is not available, there is only one option, i.e., reduce the AOA and sacrifice altitude.

Training in these airplanes is in some ways similar to engine-out training in light twins. By that I mean it is a "theory" that "one size fits all". In the real world it just doesn't.

In stall recovery training pilots are normally instructed to "recover with minimum loss of altitude". In most cases, losing more than 100 feet is a no-no that could cause you to "fail" the proverbial check ride. However, this training is usually conducted at around 10,000 feet. At that altitude, plenty of excess power is always available. So, we teach pilots to recognize the approach to stall, set a pre-determined deck angle (pitch attitude) and "power out" of the stall. This results in a "recovery" with the desired minimum altitude loss. The problem is that only works when the excess thrust required is actually available. At altitudes near the top of the flight envelope, it never is. Therefore, any recovery attempt mandates a significant altitude loss. In the CRJ that's approximately 3,000 feet. Normally this isn't taught at all or if it is, the teaching is a "briefing" and not actual practice or even demonstration. For my money, the "stall recovery demonstrations" that most training require and that the FAA wants to test, are an exercise in futility. They really don't teach much of anything but the do create unrealistic expectations on the part of the pilot.

Pilots have a Pavlov-like response in critical situations. We do what we have been "trained" to do, automatically. In the scenario of this particular event the training received simply doesn't transfer to the situation at hand. You simply can't recover with very little loss of altitude and any attempt to do so will almost certainly result in PIO (pilot induced oscillation) and secondary stalls. The information we have tells us that is most probably what happened after the first "upset."

As far as we now know from the available data, the "aerodynamic stall" that occured did NOT happen when the pusher activated the first time. In other words, the pusher did what it was designed to do, i.e., reduce the AOA and prevent the "stall" from happening. It was during the recovery attempt that several secondary approaches to stall and pusher activation events occurred until eventually an aerodynamic stall did occurr.

By the time the accident aircraft reached FL410 it was already on the back side of the power curve. Not only was it unable to accelerate, it could not even maintain minimum airspeed. Both pilots saw this but neither one of them appeared to realize what would happen next. In the summer with OAT of ISA +20 and a heavy airplane, the exact same thing could have happened at a much lower altitude. From what we have learned so far, it does not seem that they understood the principles involved. Many of the arguments on this forum appear to indicate that they were by no means "alone".

The flame-outs didn't happen as a result of the first pusher event. They happened when the PIO produced a "full stall". In other words, the pilots' response to the pusher activation, resulted in overriding the purpose of its installation and created the aerodynamic stall, which in turn resulted in the flame outs. It is likely that if the pilot flying had just gone to hands off, the aircraft would not have "stalled" and there would not have been a flameout.

Yes, the pilots did get the aircraft into this bad situation by their lack of knowledge and inattention. However, once it happened, I'm convinced that the response to regaining control and the resultant PIO was a product of their training and "rote" reaction and NOT poor airmanship. The flying pilot had virtually no experience and from all appearances, neither did the captain. Eventually they did figure it out and got the airplane flying again, but by that time they had already lost both engines. Poor training = poor performance. Let's not blame them for the poor training.

It's like the new multi-engine pilot. Over and over again he is "trained" to react to an engine failure in a certain way --- mixtures, props, throttles, flaps up, gear up, identify, verify, feather. It happens faster than I can type it, over and over again. He learns it by rote, takes a check ride and gets his multi-engine rating. A few months later he's in his turbo-charged Navajo. As he rotates for lift-off, the #2 turbo charger fails. The airplane yaws hard and he goes through the "trained" exercise. With the feathered prop the Piper won't fly and crashes off airport. In the investigation we discover that the engine never failed, we just lost a turbocharger and a few inches of manifold pressure. Yes, there was a loss of power but there was no engine failure. Had it not been for the "training" there would have been no crash and no obituaries.

In this accident inadequate training will most likely NOT be the probable cause. That will be "pilot error". However, there is no reasonable doubt in my mind that a lack of proper training was a major contributing factor in causing this accident. Yes, the pilots were goof offs and they didn't know what they were doing or why they were doing it. BUT, the training they never got was, in my opinion, a major factor in their being unable to recover from their initial mistake.

This diatribe only scratches the surface and is just my opinion. Therer's a great deal more to what really happened that night and a lot of people, besides those pilots, will have egg on their faces before this accident investigation is over.

 

[surplus1]

The SPS (stall prevention system) in this aircraft is there for more than one reason and the reasons are not the same at low altitudes vs high altitudes.

At low altitudes the wing responds to aerodynamic stall with a high roll rate; too high to meet the certification requirements. Therefore a shaker/pusher installation is required to avoid aerodynamic stall. At very high altitudes the stall characteristics are rather benign and would not require a shaker/pusher. But, there's a different problem. At high altitude it is know that airflow disruption at too high AOA produces shock waves that can disrupt airflow to the engine inlets severe enought to cause flameout. Therefore the shaker/pusher is there to prevent the aircraft not from stalling, but from operating at an AOA high enough to cause airflow disruption/shockwaves and prevent flameout. While there is only one SPS, it is there for two entirely different reasons. I'm curious -- did they teach you that in the school house?

If this were taught to line pilots (I don't think it normally is) I doubt that pilots would be "fighting" the pusher once it activated at high altitude. No line pilot (we aren't Bob Hoovers) is going to do something that he/she KNOWS will shut off both engines in a 2 engine airplane. Only test pilots and stunt pilots do that stuff intentionally. Now, if you don't know what the result would be, it's a whole different ballgame.

On top of that, there are a series of conflicting airspeeds in the QRH and the FOM. In one place (in the Double engine failure procedure) we are told that the best glide speed (engines out) is a target of 170 - 190. In another place we are asked to establish a target of 240, then accelerate to 300 -330 for a windmilling relight attempt. For an APU assisted relight, we are told that the IAS window is Vref up to Vmo and that technique was "demonstrated". I wonder who it was "demonstrated" to and why?

What you gonna do if you're holding at 12,000 AGL and 200 KIAS with the APU deferred, when both engines flameout?

Where does it tell us why these particular speeds were selected or what could happen if we choose the wrong speed at the wrong time? If we're above FL260 when the flameouts occur and elect to use the best glide speed for a while as we prepare, is that potentially dangerous? Why? Why is the target airspeed 240 and not 260 or 220? What's the reason behind that particular airspeed?

We're told that it will take about 5000 ft to go from 240 to 300 KIAS. Anybody want to guess how much it will take to go from 190 to 300?

 

[Rez O. Lewshun]

Don't know what procedures the other regionals have, but Pinnacle doesn't really require any certain mode to be used. Most of the pilots climb in VS mode above 10k because they think the speed mode isn't smooth enough. Personally, I always fly in IAS/MACH Climb mode. If you turn on Turbulence mode along with speed mode then it dampens the pitch oscillations and makes it pretty smooth.

Having flown the CRJ since 2000, I climb in PTCH mode. Most pilots question this.

PTCH mode is shunned because it is the default vertical mode. The default lateral mode is ROLL. Roll is isn't good because it can maintain a bank angle of up to 5 degrees. The logic is if ROLL is bad then PTCH is bad.

PTCH is different in that it maintains the pitch angle the pilot sets. This is better than Vertical Speed or Speed mode because PTCH mode maintains a contant angle of attack. The pilot doesn't know what AoA he/she is flying, nonetheless it is constant.

Constant Angle of Attack provides a stable, steady climb up to your flight planned atltitude. There are no oscilations and thus wasted energy. Set the CRJ 200 at 2.5 degrees NU and the aircraft will stop climbing before anything else happens. It can't stall at 2.5 NU. In Speed mode or VS mode you run the risk of exceeding the critical angle of attack if no changes are made.

Thoughts?

 

[TIS]

I beleive I read in an earlier post that the spoilers PARTIALLY deployed because of the loss of hydraulics associated with the dual engine flameout.

Ya know I'd almost buy that if it weren't for the fact that the boards are plotted as being extended 6°. That's a LOT of float without hydraulics. Any other thoughts?

TIS

 

[PCL_128]

Rez, didn't you listen to your ground/sim instructor at Pinnacle? "Don't let the plane go into Pitch or Roll Mode!!!! You'll die!!!!!!!" Seriously though, I've used Pitch mode a time or two, but it usually brings such complaints from the Captains I fly with that I just gave up on it. Have you gotten many FOs uncomfortable with it at Pinnacle since the training dept is so crazy about Pitch/Roll?

 

[PCL_128]

Ya know I'd almost buy that if it weren't for the fact that the boards are plotted as being extended 6°. That's a LOT of float without hydraulics. Any other thoughts?

TIS

The Bombardier rep testified that flight tests showed that 6° is normal float for the flight spoilers and 1-2° is normal for the ground spoilers.

 

[Rez O. Lewshun]

Rez, didn't you listen to your ground/sim instructor at Pinnacle? "Don't let the plane go into Pitch or Roll Mode!!!! You'll die!!!!!!!" Seriously though, I've used Pitch mode a time or two, but it usually brings such complaints from the Captains I fly with that I just gave up on it. Have you gotten many FOs uncomfortable with it at Pinnacle since the training dept is so crazy about Pitch/Roll?

Well of course I ask the FOs if they are ok with it. Then I give them my disertation on PTCH mode and they seem to be ok with it. If not just for interest then for the difference, they are receptive

It's really technique. Of the three CRJ operators I've flown for, PTCH mode isn't prohibited.

The reasons instructors will say PTCH mode shouldn't be used is, 'Cuz I said so.' My CRJ guru indicated that Bombardier doesn't recommend it, but I've never gotten a real reason. When I went thru factory training in YUL I never recall it being prohibited....

Any Comair or Skywest guys have any input?

 

[TIS]

The Bombardier rep testified that flight tests showed that 6° is normal float for the flight spoilers and 1-2° is normal for the ground spoilers.

Well then, there you have it! Thanks!

TIS

 

[Lear70]

PTCH is different in that it maintains the pitch angle the pilot sets. This is better than Vertical Speed or Speed mode because PTCH mode maintains a contant angle of attack. The pilot doesn't know what AoA he/she is flying, nonetheless it is constant.

True... as long as the airspeed is constant. If your airspeed slows at a given pitch angle, the AOA will inrease, and vice-versa. As long as the pitch angle is reasonable for that altitude (2-3 deg NU), you'll run out of airspeed and vertical climb rate and start descending before you'd ever stall the aircraft.

I used pitch in the Lears but I don't like the way the CRJ handles pitch mode, and I certainly don't like the way it handles speed mode (uncomfortable for the pax as it chases its tail all day), so I use vertical speed and just monitor the airspeed.

The one thing I DO use pitch mode for is extending the flaps on a Flaps 20 aircraft, IF I'm descending. The pitch moment is so extreme going from flaps 0 to flaps 20 that you'll set off the trim clacker most of the time, but pitch mode will simply reduce your rate of descent and you can switch back to v/s or speed mode and dial back in what you need. Much easier on the pax...

 

[FlyChicaga]

Having flown the CRJ since 2000, I climb in PTCH mode. Most pilots question this.

PTCH mode is shunned because it is the default vertical mode. The default lateral mode is ROLL. Roll is isn't good because it can maintain a bank angle of up to 5 degrees. The logic is if ROLL is bad then PTCH is bad.

PTCH is different in that it maintains the pitch angle the pilot sets. This is better than Vertical Speed or Speed mode because PTCH mode maintains a contant angle of attack. The pilot doesn't know what AoA he/she is flying, nonetheless it is constant.

Constant Angle of Attack provides a stable, steady climb up to your flight planned atltitude. There are no oscilations and thus wasted energy. Set the CRJ 200 at 2.5 degrees NU and the aircraft will stop climbing before anything else happens. It can't stall at 2.5 NU. In Speed mode or VS mode you run the risk of exceeding the critical angle of attack if no changes are made.

Thoughts?

I do this in the ERJ, for reasons similar to yours. Also because I can "bug" the desired climb speed, which with a quick glance gives me a good indication of if I'm off from the climb profile. I'm curious on opinions of this for both airplanes.

I keep the airplane out of IAS/MACH mode unless hand-flying (which I do up to cruise often lately), since if you fly into a headwind, such as the jetstream, the airplane will pitch up quickly and give you a huge climb rate. Then, it will drop off and nose over just as quickly. Not comfortable for the paying customers in back at all, nor does it seem like a safe maneuver at FL300+ pitching to 15 degrees!

 

[172driver]

I almost always climb in pitch mode. It is smoother, as you said, especially in really bumpy weather. All the publications recommend holding a constant pitch when penetrating a storm. I figure the same is true in any moderate or better bumps.

We all know speed mode sucks and the pitch oscillations in VS mode, though they are slight in smoother air, can't be the most efficient way to operate.

I'm at Comair and have never had a captain so much as look at me funny when using pitch mode. It's pretty common here. Now roll mode is another story...I do use it occasionally but I have gotten some reactions.

Also, pitch mode makes for the type of climb I believe the airplane is best suited for. Set 2.5 degrees out of 10,000 and it will accelerate up to 320 kts, hold a 1500 fpm climb once it gets there, bleeding the climb rate down to 500 fpm in the mid 20's. After that, you may need one more click of NU to maintain 500 fpm, trading some of your speed. The airplane will quit climbing well before it gets to an unsafe speed, unless you continue to crank in more pitch for some reason, which I don't.

 

[FlyChicaga]

Could you all explain roll mode in the CRJ? What is the max bank angle for it?

I've used it in the ERJ when evading broken buildups on the climbout for a smoother ride. Can give a rapid roll rate if used carelessly, like a damm snap roll. But if used slowly, it is much better than rolling the heading bug back and forth. Much smoother ride.

 

[172driver]

Roll mode is the default mode in the CRJ and is only used to transition between raw data and other lateral modes. There is no way to adjust it...it simply locks the FD at whatever bank angle you were at when you selected it. There is no control to steepen or shallow the bank.

For example, if you are flying raw data and select a vertical mode such as VS, the FD will sync to whatever bank angle you are currently flying. I sometimes use it when things are getting busy and bumpy, I'm established in a turn, and I feel like hand flying might not be the best option. I will simply select AP engage and the AP will default to pitch and roll mode, keeping the airplane in exactly the pitch and bank that I left it in. Before I get to my desired heading/course, I will select HDG or NAV mode.

If you select hdg or nav before you engage the AP, the airplane can get a little confused and shallow the bank, or even bank the other way, while it thinks about things.

The other time you will see roll mode engaged is when we come to the end of our flight plan in the FMS. When we cross the last fix, the AP defaults to roll and we will remain in whatever bank we were in at the time. Not a good time to fall asleep...

 

[surplus1]

PTCH is different in that it maintains the pitch angle the pilot sets. This is better than Vertical Speed or Speed mode because PTCH mode maintains a contant angle of attack. The pilot doesn't know what AoA he/she is flying, nonetheless it is constant.

Thoughts?

I have nothing against the use of pitch mode but please take a second look at what you said. I don't think pitch mode will maintain a "constant AOA" unless you also maintain a constant air speed. What you said may be true if you have enough power to maintain a constant AS at the same time and you use it.

Unless I'm mistaken, which is quite possible, when you set a given pitch attitude and airspeed the airplane "climbs" because you have more power than required for level flight. As the difference between pr and pa narrows, vertical speed will decrease. When you reach an altitude that requires all of the power either being used or available, the climb will stop. If the power is less than required to maintain that altitude, airspeed will decay and AOA will increase even though the pitch attitude hasn't changed.

Unless power available = power requiired (rather exactly) a steady state cannot be maintained and something will have to give.

 

[:-)]

I've got it. Why don't you CRJ people just hand fly to altitude? It sounds as if the airplane requires constant sheparding anyway, so just hand fly and relieve yourselves of the burden.

I think I'd rather just hand fly (act) instead of being forced to REACT to the actions of the autopilot/flight guidance system.

No kidding,
Hobbes

 

[TIS]

Why don't you CRJ people just hand fly to altitude? It sounds as if the airplane requires constant sheparding anyway, so just hand fly and relieve yourselves of the burden.

Well, with DRVSM that could get problematic. You're supposed to use the autopilot when in cruise in DRVSM airspace. It's not too much of a stretch to think that some FAA idiot would come along saying you have to use it for ALL operations in DRVSM airspace.

But that's speculative at best.

I do agree that if your jet doesn't do well in any automatic/pre-programmed mode such as those discussed, you should avoid using them in favor of simply setting a pitch and monitoring the climb for a reasonable rate of climb considering SAT/TAT and flight conditions. Most often it's the vertical modes that someone paid big dollars to get past the FAA certification group that cause the trouble. Lateral modes are generally pretty reliable and fly the plane well.

Just because a mode is there it doesn't mean it's necessarily the right thing to use and it certainly doesn't mean that it's always a good idea to use it. it's important to know your flight director controls and what they do. I saw a reference to a "click of NU" here. Understanding what that will do in a climb, a descent, and in altitude hold mode is important.

It's also important to understand how the AP interfaces with your LRN system. if you get your RNAV from an FMS, it's the FMS that actually commands the bank in order to give it control over intercept plots that it calculates.

Using an AP by rote because it's the way everyone else does it is fine as long as you're not left mystified as to what's happening. There's a book - probably online someplace. It's a good idea to read it at least once.

TIS

 

[Lear70]

The main issue with using roll mode is that you really haven't told the aircraft to do anything except hold a given bank angle.

Heading mode, used in conjunction with the TURB switch, when deviating around cells will give you a nice smooth roll rate and direct control over where you're going. Quite frankly, whenever I engage the autopilot, the TURB switch is right behind it - too many years of flying charter and corporate, I like a smooth ride.

 

[Rez O. Lewshun]

I have nothing against the use of pitch mode but please take a second look at what you said. I don't think pitch mode will maintain a "constant AOA" unless you also maintain a constant air speed. What you said may be true if you have enough power to maintain a constant AS at the same time and you use it.

Unless I'm mistaken, which is quite possible, when you set a given pitch attitude and airspeed the airplane "climbs" because you have more power than required for level flight. As the difference between pr and pa narrows, vertical speed will decrease. When you reach an altitude that requires all of the power either being used or available, the climb will stop. If the power is less than required to maintain that altitude, airspeed will decay and AOA will increase even though the pitch attitude hasn't changed.

Unless power available = power requiired (rather exactly) a steady state cannot be maintained and something will have to give.

Usually, the IAS stays the same, around 290/.70. It does start to bleed off once the jet gets to FL300+. (based on weight/ISA) It decreases, but I don't think the AOA changes too much, especially if one is operating the jet IAW with the flight release and performance charts, but then again, there is no AOA indicator to reference.

Speaking of performance charts. The CRJ chart reference climb capability that is given to pilots (usually in the QRH) to check if they can climb to any given altitude with a given weight/ISA is just one of many. It is for a specific %MAC and pack/bleed setting. IOW, it is a very generalized reference.

Lear70 indicated the same with a constant airspeed. AOA is elementry and paramount in aircraft control, yet "they" seem to keep us pilots from applying it.

I am wide open for a complete understanding... more info requested..... including links...