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Increasing Helicopter Speed

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Hello All,New to this forum, not new to MSFS however.... I've recently been bitten by the helicopter bug, and I've gotten pretty good at all of the flight dynamics to fly them.I've recently downloaded several Bell 205a Helos and find their top speed is about 45-50 knots. Even with FULL throttle, these aircraft will get up to about 50, then slow to under 40. Aircraft data states top speed over 100 knots.Where, what file or files, and how do I edit these aircraft to fly the correct speed?Thanks

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The helicopter aircraft.cfg file has sections with power and thrust scalars, use notepad to open this file and find:[turboprop_engine]power_scalar = 1.0[propeller]thrust_scalar = 1.0but without knowing how much engine power is needed to hover in ground effect, or what the maximum rate of climb is for the helicopter model(s) in question, I can't say if either of these should be adjusted, only that they can increase the airspeed by increasing power and thrust.If I remember correctly from my Air Cav days the real model 205 (UH-1D and H models) hovers IGE with about 20-25 ft/lbs of torque on the gauge at light to medium aircraft weights (Max is 50 ft/lbs gauge), which is around 440-550 SHP or 40-50% of the available engine power (T53-L13, 1400 SHP flat rated and transmission limited to 1100 SHP). At near max gross weight this would go as high as the gauge redline (50 ft/lbs) and some forward speed and translational lift was necessary if you wanted to go anywhere (good old Slick, nobody ever accused it of being overpowered!). I can't recall the maximum rate of climb for the UH-1H, but it was probably over 1000 FPM at medium aircraft weights.I seem to remember reading somewhere that the transmissions in the 205 have been uprated from the 1100 SHP rating in recent years, I don't recall the exact details, but it is possible that the Hueys still in service have more engine power available.The airfile has entries for aerodynamic drag - "Rec 1404 Helicopter Fuselage Area and Drag" has the entry "Frontal Surface Drag Coefficient". This is set at 0.4 in the default Bell 206, and this entry will definitely provide for an increase in speed from a reduction in drag if you lower the value entered there.You'll need AirEd to open and edit the airfile, you can get it here (along with other airfile editors) for free:http://perso.wanadoo.fr/hsors/FS_Soft/fsairfile.htmlRegarding the top speeds for this helicopter, Vne (never exceed speed, redline on the airspeed indicator) was 120 KIAS on the UH-1H circa 1975, the typical cruising speed was 90-100 KIAS, although this could be higher depending on the absence or presence of vertical and/or lateral vibrations in the main rotor, these vibrations (especially the lateral) made flight at higher cruising airspeeds a proposition for masochists only. For flight simulator, a cruise speed of 90-110 KIAS would be about right.A good and moderately in-depth approach to the problem would be:1. The empty weight in the [WEIGHT_AND_BALANCE] section of the aircraft.cfg file should be checked to see if it is correct, off the top of my head the empty weight was around 5400lbs, that figure should at least put you in the ballpark . 2. Check the [fuel] section of the aircraft.cfg file, the fuel capacity should be around 220 gallons/1430lbs (again, relying on memory here)3. Verify that the aircraft is producing the right amount of engine power and main rotor thrust by checking that around 50% power is needed to hover in ground effect with full fuel on board. Adjust power and thrust scalars as necessary to achieve this torque value.4. If the weight, power and thrust factors are ok, then adjust the "Rec 1404 Helicopter Fuselage Area and Drag" entry "Frontal Surface Drag Coefficient" by decreasing the value of this entry until you attain the maximum forward airspeed you want.If you aren't interested in point by point realism where the flight model is concerned, then the easiest alternative to the above would be to simply replace the airfile with the default Bell 206B airfile.Rename a copy of the 206B airfile to the airfile name of the problem helicopter you're working on, and then replace your problem helicopters original airfile with that renamed airfile copied from the 206B.Then, in the problem helicopter's aircraft.cfg make sure the empty weight and fuel entries have the same numbers entered as the entries in the default Bell 206B's aircraft.cfg file, that the power and thrust scalars are set to 1.0, and you should have a helicopter that flies like the Jet Ranger and looks like a Huey (hopefully!).

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Douglas,Thank you for your detailed reply. Sorry it took me a few days to post and say thank you. I've downloaded the program you suggested and I'll do some experimenting this weekend.Again, thank you for the detailed information and your response.Cecil

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