Thanks both of you for your replies. sure I'll practice as much as I can, on FG it is cheaper and safer than in real life ;). I'll put some screenshots on http://fgfs.i-net.hu/. (today trip: LFIR -> LFHA, with much better use of prop control and mixture, climbing and descending were almost nice ;))
cu on mp servers. Dave Perry a écrit : > On Sun, 2007-02-04 at 18:07 +0100, Sébastien MARQUE wrote: >> hi all! >> >> I really find the Piper Comanche pa24-250 from Dave Perry wonderfull! I >> use it on cvs FG-OSG. >> But as I come from c172p, I'm a little confused with the engine, >> propeller and power controls... >> >> First for a 180 miles trip I use 3/4 of the available fuel (on the four >> tanks, ~7.000 ft ASL, ~130 KTAS), I don't know if it is normal, or too >> much, I personnally think it's too much, and I misuse the engine controls. >> > First thanks for the kind comments. Second, the comment from Hal Engel > were right on. > > Concerning the egt and leaning. About a month ago, I added to the > pa24-electrical.nas code that models more realisticly the egt. With > this change, you should be able to come very close to a real leaning > procedure. If you slowly (a little at a time because the code models > "thermal" delay) pull back the mixture until it peaks at about 300+ on > the egt, then push it back in until the temp drops about 25 to 50. This > should give about 12.5 to 13.5 gal/hr fuel consumption, as in the real > pa24-250. You can browse the fuel flow in the properties list. > > I regularly get 155 to 160 knots tas in the model and in the real > N7764P. If you are not "clean" (gear up and no flaps) or if you have > poor stabilator trim and are chasing the desired altitude, then expect > lower tas. I also added a working tas ring to the asi as well as an OAT > on the left front window. To use this, get the outside air temp in deg. > C, align your altitude with the OAT on the asi and the TAS in mph is > indicated on the white scale on the asi. You should regularly get more > than 180 mph TAS. > > The "rule of thumb" that was taught when the pa24-250 was new was to run > power "square" at cruse and in all climbs run the manifold pressure > "less" than the RPM/100. So 23 in manifold pressure and 2300 RPM cruse > was common practice. > > Constant speed propellers (like on the pa24) are not well modeled in > Yasim. After some discussion on the developers list, we compromised in > modeling the prop control response. Anyone who has flown with constant > speed props will notice that the RPM on the pa24 drops too soon as you > pull back the throttle. Also, in constant rate descents such as on an > ILS GS, I use about 1 inHG less manifold pressure in the fgfs pa24 than > in the real AC. >> here's the trip: >> http://fgfs.i-net.hu/modules/fgtracker/?FUNCT=FLIGHT&FLIGHTID=10065&PHPSESSID=fde9c270fdb27c820fde750dd1c9a31e >> >> Indeed, I can't succeed to find the good way to use the mixture control >> (on the c172 I used the fuel flow keeping its value at the minimum, >> don't know if it is the good manner, btw). for now I keep it at the >> maximum (except for switching off the engine). >> >> To climb or descend I was used to play with power control on the c172, >> on pa24 it is not that simple ;). so I try to play with n/N key to >> control propeller, putting the manifold pressure at 16 (for descent, as >> described in README.pa24-250), but I don't understand the effects both >> on propeller and rpm, and my descent is not very nice... >> for climbing I push the propeller control to the maximum, manifold >> pressure too, and I try to correct climb rate using the yoke and trim, >> so I can't keep a constant speed... and climbing is not "smooth" >> (neither descent) ;) > > I think of the prop control like a manual gear shift. When going up a > steep hill, you need to downshift to get the full benefit of the power > and not damage the engine, i.e. push the prop control forward. The > throttle in both the pa24 and your car only determines how much power > you are applying. > >> I'm not a real pilot, I only fly on FGFS, so sorry if I don't use the >> good terminology for these controls (indeed I don't know it in English, >> that is a problem to find infos over the Net). >> >> Any help is welcome to explain how to use these controls fine. >> Thank you. >> > As Hal said, the pa24 rewards smooth control inputs and trim is very > important. Just keep practicing! ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier. Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Flightgear-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/flightgear-users
