December 11, 20187 yr Author 9 hours ago, JRBarrett said: The exact idle N1 you end up with can vary based on pressure altitude (field elevation) and temperature. The older N2-regulated engine computers in the Falcon 50 with -3 engines don’t have a fixed idle N1, which is why the yellow idle arc on the N1 gauge goes from approx 24 to 31. I think at ISA near sea level it would be closer to 31. The newer TFE731 engines use N1-regulated computers. Those have a constant idle N1. The computer switches on the overhead panel when the aircraft has N1 DEECS has three positions: “off” “manual” and “auto”. I think that is how they are configured on the 50EX with -40 engines. It is that way on the 900 which uses -60 engines. With N1 computers, Max takeoff N1 is automatically calculated based on termperature, so in “auto” mode, you can firewall the throttles on takeoff, and N1 will not exceed the calculated value. I’ll check our TFE731 engine manual at work later today. (The manual covers all variants). I think there is a graph that shows idle N1 vs. temperature/pressure altitude for the -3 engines with N2 computers. Our TFE731 manual doesn’t have the -3 after all - only the -20, -40 and -60 with N1,DEECS. But in any case, taxi power seems quite good in Beta 4.8 Jim BarrettLicensed Airframe & Powerplant Mechanic, Avionics, Electrical & Air Data Systems Specialist. Qualified on: Falcon 900, CRJ-200, Dornier 328-100, Hawker 850XP and 1000, Lear 35, 45, 55 and 60, Gulfstream IV and 550, Embraer 135, Beech Premiere and 400A, MD-80.
December 13, 20187 yr I noticed after a quick first test that you can fly at 4000ft with the engines at idle and the aircraft will not decelerate below 160 kts. It will just fly nice and level with the engines at idle. Is this correct?
December 13, 20187 yr Commercial Member 1 hour ago, NeilC said: I noticed after a quick first test that you can fly at 4000ft with the engines at idle and the aircraft will not decelerate below 160 kts. It will just fly nice and level with the engines at idle. Is this correct? No that is not correct. I wonder if the new flight dynamics screwed up my low altitude power settings. Will check this today. Update: The idle was at 35% N1. Should be roughly 31.4% N1 at low altitude. Adjusted the air file and now it stays at idle at lower altitude. Also this was good that you pointed this out because since we did improve the FD the gear warning for below 160kts code needed to be adjusted so the minimum throttle to disengage the warning will maintain a minimum of 160 knots. I also made the airspeed reference marker move 5 X faster for wheel and fine tune with L/R clicks. This will be handy. Edited December 13, 20187 yr by Flysimware
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