I am working on a flight control computer (Bombardier) where I got a bunch of requirements for steep approaches. All they do is 'engage steep approach' or disengage it after determining if it is safe to engage the steep approach.

Even after engaging the steep approach, if the pilot does not configure the flight properly (throttle, flap, slat settings) then it disengages the steep mode and informs the pilot.

After carefully going through the requirements, I did not find anything that the flight control computer does during the steep approach.

  1. So is all that the flight control computer does during steep approaches to monitor it and display steep engage or disengage messages?

  2. What would a pilot do if steep approach was to disengage when he reached below 200 ft? (Breaking off from steep approaches, I understand, is the result of losing some of the sensors, jamming of actuators etc..). Can a pilot 'go around' even if the altitude drops below 200 ft (decision height of CAT I landing)?

  3. Is there a possibility for the aircraft to stall while trying to descend steeply?

  • $\begingroup$ Which Bombardier product? Learjet 45? $\endgroup$
    – wbeard52
    Apr 21, 2016 at 15:11
  • $\begingroup$ Bombardier C-Series 100 $\endgroup$ Apr 21, 2016 at 15:19
  • $\begingroup$ I can't answer the question, but it sounds very similar to requirements for Cat II approaches. Just a bunch of monitoring and handling the annunciators. $\endgroup$
    – Lnafziger
    Apr 21, 2016 at 16:48
  • 12
    $\begingroup$ I hope you get some useful answers here, but I also hope you ignore them all and ask for your requirements to be updated with the answers :-) More seriously, anything you learn here may be very useful background information for you, but your requirements should be the final reference. $\endgroup$
    – Pondlife
    Apr 21, 2016 at 21:02
  • $\begingroup$ Sure,my question is - does pilot get any assistance from flight control computer or autopilot or he just hand flies the airplane. If he need to do everything by himself it seems like lot of work to me $\endgroup$ Apr 22, 2016 at 2:37

1 Answer 1


On the Airbus 318, it appears that the flight control computer does more than just monitor and handle annunciators.

In March 2006, the European Aviation Safety Agency (EASA) certified a modified control software enhancement to the Airbus A318 designed to allow the aircraft to perform steep approaches. The aircraft is the largest commercial aircraft certified by EASA for steep approach operations. The software modifies the control laws of the aircraft when the steep approach function is selected by the crew, by automatically deploying some of the spoiler panels to provide additional drag when the aircraft is in the landing configuration. It also provides alternative aural alerts to the crew and modifies spoiler deployment automatically below 120 feet (37 m) on landing. The A318 steep approach procedure allows the aircraft to perform approaches at descent angles of up to 5.5°, as opposed to the standard 3° for a normal approach.

A318 Wikipedia

The answer to your question #2 can be found in the aircraft operations manual.

The answer to your question #3 is that an aircraft can stall at any attitude and configuration. A stall is when the critical angle of attack for the wing is exceeded.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .