Hi,
I am hoping for some help making sure our simulation (www.flythissim.com) of the DFC 90 in Cirrus aircraft with v8 Entegra PFD/MFD and GNS 430 W is accurate. The questions relate to the autopilot logic I hope they are clear and unambiguous. If I have made any mistakes in the logic of the questions please correct me. If its easier t call me than write answers my cell is 1 408 835 3655 (email carl@flythissim.com)
I have seen the Fly Level button causes the autopilot to command 0 Pitch and 0 Roll and puts the autopilot into PITCH and ROLL mode, that turning on the autopilot with the AP/FD button puts the autopilot into PITCH and ROLL mode (at the current Pitch and Roll angles?) and also while coupled to the glide slope pressing the GS button puts the autopilot into PITCH mode. These are the only times I see the PITCH and ROLL modes BUT:
My question is does the autopilot go into ROLL mode if a lateral mode is 'cancelled' i.e flying along in heading mode flying a commanded turn and the pilot hits the HDG button. Does the autopilot 1. Do nothing 2. Go into ROLL mode and maintain the current roll angle 3. Go into ROLL mode and command 0 roll.
Same question for the Nav button.
Same question for vertical modes as well. If in a VS climb and the pilot selects VS doe the DFC90 1. Do nothing 2. Go into PITCH mode and maintain the current pitch angle. 3. Go into PITCH mode and command 0 pitch.
APPROACH mode. I assume you can select approach mode at any time, to increase the lateral gain. If the pilot does this and a valid ILS signal or GPS approach is NOT detected the lateral approach mode will still be engaged.
In this case if the pilot selects the APP button again is the lateral approach mode cancelled and the APP indicator extinguished?
In the questions below I have provided answers, are they correct, When established on the localizer and glide slope in NAV/APP/GS. What happens if I press APP? To the APP indicator To the vertical mode To the GS indicator Nothing, the APP/NAV/GS annunciations would remain the same, APPR mode will remain active, the autopilot coupled to localizer and glide slope, no vertical mode change
What happens if I select another vertical mode; IAS, Vs, Vs/ALT? To the APP indicator To the GS indicator The APPR annunciation would remain green and the vertical mode would switch to the new selected mode. The vertical part of APPR functionality would be cancelled and the GS annunciation would go white. At this point any auto-arming of Approach mode is suspended. (Erik was unable to answer when this suspension is removed so I am going to program it so that the suspension will be removed when the ILS signal goes invalid)
What happens if I press the ALT button? As above. To recapture the glide slope requires pressing the GS button
What happens if I press the GS button? The vertical part of APPR functionality would be cancelled, the GS annunciation would go white, the vertical mode changes to pitch mode. Auto-arming of APPR is cancelled.
If the selections above take the DFC 90 out of Approach mode and I press the ALT button what happens. Answered above but in this case the approach mode will not auto-select even if the autopilot is in Nav and there is a valid ILS signal. The user must select APPR to get approach mode back.
Do any of the answers change for an aircraft established on a GPS LPV/LNAV+V approach. No
If the GPS is in VLOC mode and an ILS then starts to be received (because the pilot just changed nav frequencies or the ILS signal just became valid) and the AP is in NAV mode what happens to the HSI selected course. Nothing, the DFC 90 does not know the ILS course, the HSI course stays where it is
If the GPS is set to automatic GPS/VLOC switching and the aircraft is on a leg where the DTK is not the same as the ILS inbound course and the pilot switches to VLOC manually what happens to the HSI selected course. Nothing, the HSI set course stays where it is, there is no auto-slewing of the HSI set course on an automatic GPS/VLOC switch.
|