Flight Model Errors

[Geofa]

This one's got 285 HP and should be able to take off in less than 1500 feet for sure. I've made some edits and its pretty decent now. I think I'll stop playing with it and enjoy it until they release some patches.

Takeoff depends on density altitude, winds, and load. Any change of those variables will change the takeoff distance.I am not saying that it would not be unable to takeoff in 1500 ft. but that would be under very specific combinations of the above-most likely full gross, 59 degrees and 29.92 pressure. Any change of these variables can change the takeoff distance by quite a bit.A performance table is really necessary to determine what is proper.

[Geofa]

Takeoff depends on density altitude, winds, and load. Any change of those variables will change the takeoff distance.I am not saying that it would not be unable to takeoff in 1500 ft. but that would be under very specific combinations of the above-most likely full gross, 59 degrees and 29.92 pressure. Any change of these variables can change the takeoff distance by quite a bit.A performance table is really necessary to determine what is proper.

I just checked some web sources-it lists takeoff to clear a 50ft. obstacle at 1769 ft. Add 20% for a test pilot doing the test with a brand new aircraft engine and we come up with 2122.I just set myself up at 3da (2510) where I was based with my Deb and ran a few tests at 59F and 29.92 and no wind.I was able to make it off every time and clear the trees in the sim. It appears to me it may be slightly light e.g it could pull off a little sooner-but it is pretty close. Make sure if you tweak it you do not do it by much. It should be able to pull off before the end of the opposite displaced threshold.

[DavidP]

I just checked some web sources-it lists takeoff to clear a 50ft. obstacle at 1769 ft. Add 20% for a test pilot doing the test with a brand new aircraft engine and we come up with 2122.I just set myself up at 3da (2510) where I was based with my Deb and ran a few tests at 59F and 29.92 and no wind.I was able to make it off every time and clear the trees in the sim. It appears to me it may be slightly light e.g it could pull off a little sooner-but it is pretty close. Make sure if you tweak it you do not do it by much. It should be able to pull off before the end of the opposite displaced threshold.

What trim are people using? My real world training in the A36 Bonanza called for 6UP trim if the load was 2 in the front seats. If you had a load, reduce this to 3UP. The Bonanza is quite nose heavy with that big Continental up front. I see a screenshot above with trim at zero.RgdsDavid

[rossdh]

I've been flying the Bonanza for quite a few hours now and in that time I've made a few changes to .cfg file, eg. increasing the prop scalar to 1.0 rather than 0.80 (which give great t/o performance btw but unrealistic cruise speeds) but I've just returned to the default .cfg. Reason being is that I found this info Bonanza Performance Specs. The more I think about it the more I think it's right but I can't confirm as I fly only a Chipmunk and in no way is that a comparable aircraft.

[rossdh]

Just tried getting out of Concrete Mun 3W5 (2720ft long) with 4 180lbs people on board, 19lbs of luggage, full fuel on a standard day ie 29.92, 15 degrees C nil wind and it took the full length but got off fine. This was using the default .cfg file. It probably could be slightly better but every aircraft, even of the same type, will be different.

[kiwikat]

Just tried getting out of Concrete Mun 3W5 (2720ft long) with 4 180lbs people on board, 19lbs of luggage, full fuel on a standard day ie 29.92, 15 degrees C nil wind and it took the full length but got off fine. This was using the default .cfg file. It probably could be slightly better but every aircraft, even of the same type, will be different.

Gee I'd hope you could get off the ground on a 2700 foot runway when the plane's ground roll is 1000 feet... If it took the whole distance that's way too much!You were flying it heavy so it makes sense that it took more than the 2400 feet it took me and the posted 1000 feet amount. However my plane wasn't anywhere near as heavy and it still took almost as long for the rear wheels to get off the ground. I'm not talking about the 50 ft. length.If you increase the propeller thrust you have to increase parasite drag to make cruise speeds more realistic. A couple of us have done this with our tweaks.

[rossdh]

Gee I'd hope you could get off the ground on a 2700 foot runway when the plane's ground roll is 1000 feet... If it took the whole distance that's way too much!You were flying it heavy so it makes sense that it took more than the 2400 feet it took me and the posted 1000 feet amount. However my plane wasn't anywhere near as heavy and it still took almost as long for the rear wheels to get off the ground. I'm not talking about the 50 ft. length.If you increase the propeller thrust you have to increase parasite drag to make cruise speeds more realistic. A couple of us have done this with our tweaks.

What have you increased the parasite drag to? And also the prop scalar.

[Geofa]

Gee I'd hope you could get off the ground on a 2700 foot runway when the plane's ground roll is 1000 feet... If it took the whole distance that's way too much!You were flying it heavy so it makes sense that it took more than the 2400 feet it took me and the posted 1000 feet amount. However my plane wasn't anywhere near as heavy and it still took almost as long for the rear wheels to get off the ground. I'm not talking about the 50 ft. length.If you increase the propeller thrust you have to increase parasite drag to make cruise speeds more realistic. A couple of us have done this with our tweaks.

You seem to be stuck on that 1000 ft. ground roll figure. As I have mentioned-these "published" figures are wildly optimistic. For instance the same source lists my aircraft as capable of flying 200 knts. (it is not) and my cruise speed as 191 (180 with older engines and 186 with new), a service ceiling of 19,700 (maybe if you had the entire day to make it up there) etc. Add at least 20 % to these figures if you want reality.http://forums1.avsim.net/index.php?showtopic=283655&hl= <edit>I just pulled up a source who is not me (and there are lots of them):http://whitts.alioth.net/Pageb11About%20Ai...ft%20Speeds.htm"Notice:"Tests have shown that takeoff distances of older aircraft can be from 15 to over 40 percent longer."

[ryanbatc]

What trim are people using? My real world training in the A36 Bonanza called for 6UP trim if the load was 2 in the front seats. If you had a load, reduce this to 3UP. The Bonanza is quite nose heavy with that big Continental up front. I see a screenshot above with trim at zero.RgdsDavid

I can't get it off at 80 kias unless I have 3U in...

[Guest]

Is it correct that the approach has to be done at a rather high speed? I have to keep her at 90 otherwise I just fall out of the sky. It feels quite fast. But then I am used to the C82RG and the C185F lately, which are slower of course (I can do the approach at 60 all the time). Funny thing is that as soon as I start to flare in the Bonanza, she suddenly doesn't want to come down and floats on longer than you'd excpect aftre the fast approach!

[rossdh]

Is it correct that the approach has to be done at a rather high speed? I have to keep her at 90 otherwise I just fall out of the sky. It feels quite fast. But then I am used to the C82RG and the C185F lately, which are slower of course (I can do the approach at 60 all the time). Funny thing is that as soon as I start to flare in the Bonanza, she suddenly doesn't want to come down and floats on longer than you'd excpect aftre the fast approach!

The speeds I use are 105kts downwind, 85 on base to final, 80 on final and let it slow to 70 on crossing the numbers OR 90 - 95 on long final, 80 on final and again let it slow to 70 on crossing the numbers.

[ryanbatc]

I have issues slowing this thing down. If I'm flying at 170 kias, and cut the throttle, it takes about 3 miles to slow to 120... is that right?

[Bert Pieke]

What trim are people using? My real world training in the A36 Bonanza called for 6UP trim if the load was 2 in the front seats. If you had a load, reduce this to 3UP. The Bonanza is quite nose heavy with that big Continental up front. I see a screenshot above with trim at zero.RgdsDavid

The supplied documentation (Pre flight Checklist) calls for 3UP with only front seats occupied.

[DavidP]

The supplied documentation (Pre flight Checklist) calls for 3UP with only front seats occupied.

The A36 must be slightly different to the F33 as my POH is as I specified.

I have issues slowing this thing down. If I'm flying at 170 kias, and cut the throttle, it takes about 3 miles to slow to 120... is that right?

That would not surprise me. Actually I was actually taught to allow 5nm to slow for approach.David

[Geofa]

Is it correct that the approach has to be done at a rather high speed? I have to keep her at 90 otherwise I just fall out of the sky. It feels quite fast. But then I am used to the C82RG and the C185F lately, which are slower of course (I can do the approach at 60 all the time). Funny thing is that as soon as I start to flare in the Bonanza, she suddenly doesn't want to come down and floats on longer than you'd excpect aftre the fast approach!

Yes! Bonanzas a slick, and lower the nose and they gain speed very quickly.As for approaches-do it by the numbers. Gradually pull the manifold 1" of a time from cruise so that when you get into the pattern or the downwind/vectors for the approach you are at 17" in the summer and 15" in the winter. Leave the prop at cruise settings. This should take you to the top of the flap speed. When intercepting the glidslope-merely put the gear down-that will give you a 500 fpm descent-you may have to retrim a little. Some use flaps at this point-I prefer not to. When you have the runway made, drop the flaps and slow her down to 90<edit> ( whoops-my plane was in mph so aprrox. 75 knts)-prop full in.

I have issues slowing this thing down. If I'm flying at 170 kias, and cut the throttle, it takes about 3 miles to slow to 120... is that right?

You don't want to cut the throttle but plan well ahead and pull 1" of power gradually so you are at the speed you need when you need to be. You have to plan quite a ways out.