V0.5.0 flight dynamics improved



  • IMHO V0.5.0 flight dynamics are the best yet. I've only flown for 30 mins so take these as first impressions.

    PROS

    Engine out performance is much closer to real life. I plan for 1.5 miles glide for every 1,000 ft (gear up, 90 KIAS) and this version of the model comes very close to that. I can now kill the engine on takeoff at 900 ft and easily make it back to the runway. Real life, with 0 reaction time to the engine out at 900ft AGL on takeoff, I can just make the turn back and land on the departure end of the runway (no wind). This is a big deal to me as I find great value in being able to practice instrument approaches and engine out landings in the simulator. Before, the glide ratio was too low and it made no sense practicing engine out landings.

    The plane trues out at 134kts TAS at 6500 ft. IMHO, that's perfect.

    Plane picks up 8 knots when you nose over at 6500 and descend at 500 f/m at 75% power. Should be 16ish, but heck, I understand the compromises involved in tuning, so I consider this reasonable and not a distraction.

    CONS

    I am pleased I can get 134 kts TAS at 6500 ft which implies reasonable modeling of power & drag. Fuel flow is too low however. On climb at 25" MP and 2500 RPM, Fuel flow should be 16-18g/h. Fuel flow gauge shows 12ish g/h. Fuel flow in general seems to be derived, or at least limited, by the power the engine is producing. This is not accurate. The only impact is that range and endurance will be artificially high. If you are not flying 6-7 hour flights, you wont notice it.

    Next flight I'll check time/distance to climb, service ceiling, and play with power settings to see if I can get same TAS using the RPM/MP/Power table entries for 2500 rpm and 2200 rpm at 65% power.



  • At 6500ft level flight I cannot go past 23"MP even at full throttle. How are you achieving that?



  • @BernieV Can't test it now. I would be interested if the fuel flow does match with the power settings table in the POH now in cruise. When I tested it the fuel flow was way too high.



  • The power modeling looks reasonable. (leaned to 100F ROP for all data points)

    f0a59b1e-f717-4b5f-9199-b2415e2beb4f-image.png

    The service ceiling test showed just under 200 ft/min climb at 15,000 ft at 2700 lbs, FT, max RPM in green arch, and leaned to 100F ROP every 1000 ft. Service ceiling is defined as the altitude where the plane climb performance slows to 100 ft/min. That close enough all things considered.



  • @BernieV said in V0.5.0 flight dynamics improved:

    The power modeling looks reasonable. (leaned to 100F ROP for all data points)

    f0a59b1e-f717-4b5f-9199-b2415e2beb4f-image.png

    The service ceiling test showed just under 200 ft/min climb at 15,000 ft at 2700 lbs, FT, max RPM in green arch, and leaned to 100F ROP every 1000 ft. Service ceiling is defined as the altitude where the plane climb performance slows to 100 ft/min. That close enough all things considered.

    Did you notice if this update fixed any of the engine start issues, or the speed being tied to RPM instead of engine power output?



  • @pilot53 comparing rows 2 and 3, you can see 65% power being generated with two different RPMs with same fuel flow and TAS. Comparing rows 1 and 2 shows different power achieved with the same RPM and different MP. That's a significant improvement over the last version. I don't think they did anything to improve engine start behavior.



  • @BernieV That sounds good, thanks for checking it out and reporting your results here. I think I'll take it back out of the hangar soon and try out this new version.



  • @BernieV This is what you should have seen, based on the performance charts.
    a23feb5d-2d33-4a7f-8ef4-76b0bca92e45-image.png