B1900D Fuel flow to TAS question

[Guest danowat]

Hi,The manual states that you set the cruise speed via the fuel flow, the figures given are 450lbs fuel flow gives 280TAS and 280 fuel flow gives 230TAS.I have completed a few flights now, and using the above fuel flows I cant get anywhere near the quoted TAS figures, with 450lbs I get 240TAS and with 280lbs I get 200TAS.Any help please?CheersDanny Watkins.

[Guest rog74]

Danny,What's your MSL? And which Sim (2002/2004)Cheers,Roger

[Guest danowat]

Hi Roger,I am usual at about FL150, and I am using 2004.CheersDanny Watkins

[Guest Spilot]

Can someone tell me what torque percentage to use at verious altitudes. Thats the problem with setting by fuel flow, unless you are at same temp. and altitude, the results will be different. Expecially since you are flying lower at 15,000, when the manual talks about 25,000. I found around 600 or 550 will give you the results needed for high cruise and about 500 for economy at lower flight levels. Is this correct settings?Adam Spilot692000@yahoo.com

[Guest rog74]

Danny,I just took a test flight and I was able to do 213IAS @ FL150 w/450 fuel flow, so the numbers are close to spot.Couple things to remember, don't use the sims calculation for IAS to TAS. Microsoft flight sims have never modeled atmospherics very well. Things like density altitude and OAT have little meaning in these sims. Just use the general 2% for every thousand above rule to calculate TAS.Now, if you cannot achieve 213IAS @ FL150, don't forget about prop and conditioning.Once again, the airspeed gauge should be set to IAS. Ignore any TAS reading you get from it, (i.e.: checking the TAS box in realism settings) for it will be erroneous.You should be able to hit 213IAS (279TAS) at 15,000 in FS2004.Good Luck,Roger

[Guest danowat]

Hi Roger,Many thanks for your help, thats interesting, I was reading the TAS off of the JL2 TAS display, could it be that as the microsoft IAS to TAS is not totally correct this would aslo make the JL2 one incorrect?.I'll have another look tonight when I get in from work, the props and conditioning are set as per the insturctions.I'll see if I can get 213IAS.Once again thanks for your help.Adam...as far as I am aware the torque reading at cruise is not relevent (unless its higher than 96%), cruise power is set using the fuel flow, 450lbs for high speed cruise, and 280lbs for economy cruise, this is only as I understand it, so if this is not correct please someone correct me ;).CheersDanny

[Guest rog74]

Danny,One other thing. I just took a look at the manual and there are some curious numbers in there. Like the 888lb/hr fuel burn at FL200. The gauge doesn't extend that far.Could be a factor of the gauges being that of the default King Air. Could be an error. Either way, I wouldn't stress over the numbers, as PMDG has said that this package's systems were not modeled to spec.Cheers,Roger

[Guest danowat]

Hi,I also notice the it (the manual) states the #### shouldn't exceed 715 degrees, but take a look at the #### gauge at cruise.LOL, looks like I can't say T.I.T. without the dots, oh dearCheersDanny.

[Guest rog74]

Close, but no cigar :-)The manual states that the EGT should not reach over 715C. The T.I.T is different.EGT: Exhaust GasT.I.T: Turbine InletInlet temp is usually much hotter than exhaust.Cheers,Roger

[Guest danowat]

Ahhh, my bad.I tell ya what, I won't worry about the figures too much, and I'll get back to flying this beauty ;).CheersDanny.

[Guest Spilot]

I am not customed to the b1900d or the engines so I do not know the actual settings,I just know from the Saab 340B that you set thrust using torque. they have a sheet with a table that shows for temp and altitude the torque settings. Just thought the b1900D was the same but maybe not. But wouldn't the fuel flow change at different temps and alt so that cannot be always the correct fuel flow setting right? Well just what I know if anyone can tell us further I would appreciated it since I am just guessing!Adam Spilot692000@yahoo.comhttp://www.precisionmanuals.com/images/forum/1900driver.jpg