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I'm gonna take simulator check for new-hired co-pilots.

The company will do simulator test in A220 for new-hired copilots. Their applicants have no experience in jets, have experiences only in single or multi engine props. (like C172, PA44)

Thus, there's no way to experience A220, cuz that model is not famous, so there's no simulator programs or place to experience.

But I found out that much differences are existing in A220. I'm trying to practice with MSFS or XPlane with A320 / B737 and A320 FTD.

There are several curiosities in control logic.

  1. A220 has TOGA switch in the thrust levers, underneath the handle of it. But, in many videos taken in the cockpit of A220 while taking off, I found that pilots do not push toga button. But, I can see thrust levers are automatically set to Takeoff Thrust position. How can they do that? Is there any button that pilots should press while taking off?

  2. A220 has weird control logic, speed trim. I failed to find any jets who have speed trim switch. Thus, I understood speed trims will fix the trimmed speed, so pilots have to change their speed trims only they want to change their target speed. But, you know B737, B747 or other boeing jets who have trim pilots should continuously change their trim while changing their attitude. In this part. when changing the attitude, what logic will be executed in A220? In speed trim at 210 KIAS with 0 FPM and 50%N1, in this situation, if a pilot commands back pressure on sidestick without changing thrust, airplane will decelerate. In turn, if a pilot returns his sidestick to neutral position, the airplane pitches down by speed trim system? Thus, if a pilot wants to climb, he should command back pressure on sidestick plus increase thrust?

Question 2 is the hardest part to understand ;(

Thanks for answering.

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1 Answer 1

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With an autothrottle system, you arm the autothrottle system with a button on the glareshield, and just advance the thrust levers until the AT system takes them over. There are servos in the console that drive the trust levers. The AT system sets power for you and sets the Flight Director to Takeoff Mode. You would only use the TOGA buttons if taking off without autothrottle.

The trim speed bug (the blue bug on the speed tape), was a new feature for the C-Series program, intended to reduce workload when hand flying. You trim to a speed for a given configuration (speed is a proxy for angle of attack) in any airplane. Jets with trimmable stabilizers don't trim like a light aircraft with an elevator tab. Instead of the control column moving to a new hands-free position when you trim as with a tab, the neutral position of the column is always in the same spot. So if you are holding elevator, you apply trim, and back the elevator off to neutral and see if the trim was enough. If not, you reapply elevator and trim again, repeat. In actual practice if you are holding the column aft of neutral, you blip the trim and ease it forward at bit, blip again and ease it forward some more, and repeat until the pitch attitude is held with the column at neutral.

Same with a side stick. Neutral is always at the same spot.

With the trim speed bug feature, you run the blue bug with the trim switch to the speed you want on the speed tape, and the FBW will set the stab to give hands-off flight at that speed for you, taking out the guesswork and gradual tweaking to get the trim right. If you're hand flying and slowing to 200kt, you don't have to pitch to 200kt and then play with the trim switch going blip-blip-blip until you can let go of the stick and it'll hold the speed/attitude, you just drive the blue bug to 200kt and the airplane sets the stab for you for hands off flight at that speed.

The airline isn't going to expect you to know anything about the A-220. You will be told to perform a series of maneuvers, knowing that you don't know the airplane, and the evaluation pilot sitting with you will do stuff for you that are aren't expected to know, and will likely tell you, "Don't worry about this function or that function, I'll take care it; you just fly". They will be looking for basic flying skill, and also observing how fast you catch on to something new and unfamiliar, plus any signs of attitude or personality issues.

That being said, if they see that you've gone to some trouble to learn the aircraft, it won't hurt, so learn as much as you can all the same.

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  • $\begingroup$ Wow! Thanks for detailed answer. But, you know I will let not to use autothrottle during the whole checkride. Thus, my curiosity is when my airplane is trimmed at 200 KIAS, and I've commanded to increase airspeed to 210 KIAS, if I don't increase thrust and only applies nose down trim (to increase trimmed airspeed), what will happen? Dose airplane maintain previous pitch attitude or command to pitch down for acceleration? (Presumes that Autothrottle is OFF) $\endgroup$
    – moon
    Jan 21 at 7:21
  • $\begingroup$ And.. Second one, when I want to climb with 200 KIAS (trimmed with 200 KIAS), what if I don't increase thrust and only apply back pressure on sidestick for changing pitch attitude and return to neutral position, does the airplane automatically pitch down to maintain 200 KIAS or maintain newly increased pitch attitude? $\endgroup$
    – moon
    Jan 21 at 7:23
  • $\begingroup$ If the thrust is constant and you raise trim speed from 200 to 210 kt, the airplane will pitch down to maintain 200 kt. It works the same as a regular stab trim; blip nose down trim, and the plane will pitch over to maintain a new speed based on the changed stab setting. It's just that with the C-Series trim bug, you know exactly what revised trim speed will result. In the C-Series there is a compromise between the Boeing pilot-more-in-the-loop FBW logic anthe Airbus pilot-less-in-the-loop FBW logic. I don't have a A-220 type rating, but spent a bit of time in the development sim years back. $\endgroup$
    – John K
    Jan 22 at 1:36
  • $\begingroup$ If trim speed is set to 200kt, and you pitch up without changing thrust, and the plane slows down, if you just let go, it will return to 200kt. It doesn't auto trim to a new speed if you are hand flying it. You might get briefed on the ins and outs of the trim. $\endgroup$
    – John K
    Jan 22 at 1:39

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