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ShaunSAP

High thrust requirement for taxiing fix?

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Thanks Bjoern! Damn I should have jointed this forum 12 years ago... getting more help than I could ask for. I found the issue I think. 

Also the reason I had a lack of thrust is because I realised CFM56-7Bs are all rated at ISA+15. I adjusted the temperature settings and managed to get the correct thrust by adding about 6.5% to the 1506 chart.

Creating a mach chart was difficult but in the end I thought it would be similar to the static chart but with a multiplier. First I tried 2x. This made the MTOW aircraft rocket up 41,000ft. Then I tried 1.1x and could barely make 15,000ft. I went back to 2x and observed my cruise n1, which was only 75% N1. I adjusted the multiplier so it would match a cruise n1 I wanted. Now the fully loaded aircraft cruises at 89%N1, which gives a little leeway if there are winds. I've seen images on Google of 737s cruising between 91.5% N1 and 85%N1.

The climb is also pretty realistic; takeoff with 96% N1 for a 24k takeoff. At 1500ft this reduces to 92% up to 15,000ft (the autothrottle momentarily derates to 90% which is favourable) and then raises back up to 96% to cruise.  Then the 300knot climb is about 2500ft/m at FL180, down to 1,000ft/m past FL350 by holding N1 at 96% at mach 0.76.

Then I tried a landing. Didn't have that pitch issue anymore so I don't know what it was. Tested a 40 flaps approach, holding Vref+5 at just below 65%N1, which is correct. This was just below MLW.

I'll have to test lower payloads tomorrow, but so far I'm very proud of what I've achieved in such a short time. Also things to do is adjust the fuel flow/throttle speed chart, and then make sure N1 matches N2. It matches at idle on the ground but I'll have to find some other data for higher settings.

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The only method I found for matching N1 and N2 at higher RPMs is by looking at cockpit photos or videos and assuming gross weight.


7950X3D + 6900 XT + 64 GB + Linux | 4800H + RTX2060 + 32 GB + Linux
My add-ons from my FS9/FSX days

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Trying to edit table 404 now... CL/AoA to bring down the AoA a little bit. Any way to add more nodes in AAM? Can't seem to import tables into AAM and can't edit Airs with notepad. 

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I've seen the thread on FSDev.

 

Note that table 404 is a fixed size, i.e. you can't add more points.


7950X3D + 6900 XT + 64 GB + Linux | 4800H + RTX2060 + 32 GB + Linux
My add-ons from my FS9/FSX days

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AAM states 404 can have a maximum of 47 points. I've looked at PMDG's 404 and they have a damn load of points... 

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