January 8, 20242 yr With my MCP unit on from CPflight at times when I change flight levels, lets say to climb, the plane starts to climb, pitching up on vert speed needle, but then, the plane will pitch downward, then come back upwards and so on and so on. Anyone know why this happens. Also, at times when I am descending, and I set speed reduction in AT, because I am desending, the idle goes only to 40% N1 and speed starts to increase a lot instead of coming down to the set lower AT speed. Anyone know how to adjust it so idle goes to like 20% N1 like when just on start up? I use P3d v4, Spadnext, Project Magenta, and CPflight MCP unit.
January 9, 20242 yr What airplane? 20% N1 at idle on pretty much any jet engine operating at altitude is very low. If you're accelerating in a descent, it's probably because you have too high a descent rate set. Think of it like a sled going downhill--the steeper the hill, the faster you go. Bob Scott | President and CEO, AVSIM Inc ATP Gulfstream II-III-IV-V Sys1 (MSFS20+24/XPlane12+11): AMD 9800X3D, water 2x240mm, MSI MPG X670E Carbon, 64GB GSkill 6000/30, nVidia RTX4090FE Alienware AW3821DW 38" 21:9 GSync, 2x4TB Crucial T705 PCIe5 + 2x2TB Samsung 990 SSD, EVGA 1000P2 PSU, 12.9" iPad Pro Thrustmaster TCA Boeing Yoke, TCA Airbus Sidestick, Twin TCA Airbus Throttle quads, PFC Cirrus Pedals, Coolermaster HAF932 case Sys2 (P3Dv5/v4): i9-13900KS, water 2x360mm, ASUS Z790 Hero, 32GB GSkill 7800MHz CAS36, ASUS RTX4090 Samsung 55" JS8500 4K TV@60Hz, 3x 2TB WD SN850X 1x 4TB Crucial P3 M.2 NVME SSD, EVGA 1600T2 PSU Fiber link to Yamaha RX-V467 Home Theater Receiver, Polk/Klipsch 6" bookshelf speakers, Polk 12" subwoofer, 12.9" iPad Pro PFC yoke/throttle quad/pedals with custom Hall sensor retrofit, Thermaltake View 71 case, Stream Deck XL button box Sys3 (DCS/P3Dv4/ATS/ETS): AMD 7800X3D, MSI MPG X870E Carbon, Noctua NH-D15S, 64GB GSkill 6000/30, EVGA RTX3090 Alienware AW3420DW 34" 21:9 GSync, Corsair HX1000i PSU, 4TB Crucial T705 PCIe5 + 2TB Samsung 970Evo Plus, TM TCA Officer Pack, Saitek combat pedals, TM Warthog, TM RS300 FF wheel/pedals, Coolermaster HAF XB case
January 9, 20242 yr Author Hi Bob, I am using Project Magenta's 737-800 model. During MCP AT I can only get 40% N1. On start up I do get around 20%. Because the plane speeds up during decent with AT, I usually try just 800 fpm with VS. Do you know how I can get the PM MCP AT to give me 20% during flight if needed? Randy Edited January 9, 20242 yr by Randy
January 10, 20242 yr Ground idle is usually lower than FLIGHT IDLE. I have not the exact values present but FLIGHT IDLE in a 737 in approach configuration depends on N2 flight idle but could be around 32% N1... Edited January 11, 20242 yr by jcomm Flying gliders since 1980 Flightsimming since 1992 AMD Ryzen 5600x, 32GB RAM, GPU Nvidia RTX 3060 Ti 8 GB, 1 TB and 500 GB nvme2 SSD drives, HP 27" 60Hz LED monitor @ 1920x1080, T16000, Hotas from old X52 Pro, Saitek Combat Rudder Pro (2010 model)
January 22, 20242 yr Hi, I have Project Magenta and Airbus full setup. I used to have same kind of up and down pitch behavior during climb. Past years I have noticed that the model you use and some parameters will affect autopilot. There is manual but quite limited info about what values and how they affect considering ini of cfg files. Also support is pretty random as far as I have experienced. Do you use exactly recommended aircraft model and FMC type file from PM update page? Newest builds? In P3d you have aircraft folder that includes your preferred 737 aircraft. There is aircraft.cfg file. What do you have in those lines : aileron and elevator effectiveness? What about pitch stability setting? What is you Thrust scalar value? I know nothing about PM737 software, but Airbus has possibility to use either FCU autopilot parameters to control pitch and bank or special PmFBW (fly-by-wire) software. I use FBW because it has more sophisticated control options over autopilot. Yours, Markus
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