AI landing distance

smoky · Post by **smoky** » 19 Dec 2008, 23:11

Hi,
as 95% of my simming is on the c9f104, I set up a flight of 4 AI f104's to fly Rimini-Ghedi-Rimini in order to practice formating on them. The problem I can't solve is the landing at Ghedi...and the recovery back to Rimini. The AI F104's land as though they've trapped the wire in an arrested landing...stopping within a few feet, then take an age to saunter down to the first exit, causing the following aircraft, which in in about six mile trail, to G/A. I've lowered the braking force in the .air file, and in the aircraft cfg. but it did'nt make a jot of difference. Any pointers on if and how it can be done would be very welcome.

Russell.

Ford Friendly · Post by **Ford Friendly** » 19 Dec 2008, 23:59

Edited to remove incorrect information as response was due to a misread of the OP's post.

GrahamS · Post by **GrahamS** » 20 Dec 2008, 05:52

Taxi speed is NOT set in the FS9 cfg, it is a setting in a dll file and I wouldn't recommend messing in there unless you know exactly what you are doing...

The original question relates to stopping distance, not taxi speed, and that is a function of the FDE. Without knowing which aircraft model and FDE set it is not possible to advise further. I am not aware of a true AI F104?
It sounds as though this one has the super brakes applied for some reason but the file name would be required?

smoky · Post by **smoky** » 20 Dec 2008, 09:10

thanks for the swift reply. The F104's are from a Memmingen scenery by Klaus Jone... on Avsim...the F104 is credited to Rey Lopez, Gunter Kirchstein, Erick Cantu, Gary Smith, Dennis Seeley and repainted by Andreas Kruschwitz. I used it because, as noted elsewhere on the forum, AI 104's are as rare as hens teeth. It's an age since I had that scenery installed, and only recently dug it out to extract the 104's. This morning, I remembered they had issued an update for the 104's, so found that, and installed it. They now land better...still too quick, but certainly not the carrier style trap as before. Still needs the braking force reducing so as to reach the exit in a more timely manner.

Russell.

paul day · Post by **paul day** » 20 Dec 2008, 09:35

There is an ai F104 available at UKMIL with AMI textures. I don,t know if it is free to all or you need to become a member, drop them a line.

Regards Paul Day.

smoky · Post by **smoky** » 20 Dec 2008, 09:56

Thanks for that Paul. I tried to get that last night...but members only. I'm a bit pushed for time today, but will try to sign up later.

Russell.

BLACKCAT · Post by **BLACKCAT** » 20 Dec 2008, 13:29

In the aircraft config file, reduction of the 'spoiler_limit=x' value will increase the roll-out distance above 100kts (this will work irrespective of whether the aircraft model has/displays spoilers, I believe).

Another parameter is the 'min_throttle_limit=-0.xxxx' which has some affect in the speed range 100-30 kts. The higher the negative value the more aggressive the reverse thrust is.

The last parameter is 'toe_brake_scale=x.xxx' and a value of 0.25 will produce a gradual speed reduction towards taxi speed.

The gentleman who produces the flight dynamics for MAIW models has done some excellent work and it would be really helpful if he would share is knowledge of how to make these AI birds fly properly with the rest of the community.

Firebird · Post by **Firebird** » 20 Dec 2008, 14:00

Another factor allied to the minimum throttle is the weight of the aircraft. When you have a flyable aircraft you will always have throttle, even idle produces something in the region of 30-40% for most aircraft, so it offsets the weight.
However for AI its throttle goes to 0%, ignoring thrust reversers, and so the aircraft will slow a lot quicker. This is why you will notice that a lot of AI FDE's have the weight a lot less than the actual aircraft, and they counter this by also reducing the thrust as well.
Please note that its never normally as easy as reducing the weight and thrust, as a reduced weight will affect how the aircraft flies.

Its a very complicated balancing act and you will find that most AI FDE people start with a dedicated AI FDE and amend it to fit the aircraft rather than amend the flyable one to fit the AI.

smoky · Post by **smoky** » 20 Dec 2008, 17:13

Thanks for the advice. I've been experimenting a bit...but have come to the conclusion that I don't know what the hell I'm doing. What confuses me is, I have two Tornados from the Italian package flying with the F104's (highly realistic touchdown and roll out...well done MAIW ) Trouble is, they stop briefly about a yard past the first exit, so take just as long to clear the runway by taxying to the 2nd...as the F104's take to taxi to the 1st exit through stopping too quickly. The Tornados have the braking force set to maximum in the .Air file...and I upped the brake force in the cfg.file from 0.07 up to 1.00. They still stop in exactly the same spot. The f104 has the braking force set to minimum in the .air file, and I moved it down to zero in the cfg. Not a jot of difference in the stopping distance. Thanks for the help...but I think I'll leave it to the experts.

Russell.

aerogator · Post by **aerogator** » 21 Dec 2008, 11:14

then take an age to saunter down to the first exit, causing the following aircraft, which in in about six mile trail, to G/A.

The FDE is all witchcraft to me but there is a program called "AISpeed" available at Avsim (I believe the author is Andy Robinson) that will change your taxi speeds but it does it across the board, not just for one a/c. Still very useful I think.

Oh, and BTW, it's found in the FS2002 stuff I think.

Ford Friendly · Post by **Ford Friendly** » 21 Dec 2008, 12:12

aerogator wrote:
then take an age to saunter down to the first exit, causing the following aircraft, which in in about six mile trail, to G/A.

I am glad to see someone else keyed in on the same bit of the original post I did.

smoky · Post by **smoky** » 21 Dec 2008, 17:23

Thanks for the replies. Can't remember the details, but I seem to recall reading somewhere that altering the taxi speeds can cause other problems, but I don't know enough about the subject to make a legitimate comment. As I see it...my problem is caused by the Tornado's slowing to taxi speed JUST after the 1st exit, entailing a long taxi to the next exit...and the F104's slowing way too quickly, giving them an almost equally long taxi to the 1st exit. What I was hoping to do was shorten the Tornado's landing run by about a yard...and lengthen the F104's to around the same distance...so they both quickly take the first exit. NOT alter the taxi speed.

Russell.

Ford Friendly · Post by **Ford Friendly** » 21 Dec 2008, 17:40

Um, nevermind.... another post edited out by myself.

Firebird · Post by **Firebird** » 21 Dec 2008, 17:59

You can do two quick things to produce a result.
One you can increase the weight by a 1k or so, but you will alter the flight dynamics its just a case of whether its adversely or not.

The other thing is to alter the min_throttle_limit to a greater negative number, this will increase the amount of reverse thrust.

What I will say though is that what will make it ok at one base will mean longer times on the runway at all other bases. I have the same problem at Marham and decided to leave it as it was for that very reason.

smoky · Post by **smoky** » 21 Dec 2008, 19:50

I really appreciate all the comments and advice I've received. However, although the F104's fly OK, and are more than suitable for the purpose...their landings leave a lot to be desired...they almost nosedive onto the runway. Given my very limited knowledge on these things, I think I'm better leaving well alone. I'd probably finish up making them un-flyable. I've now solved the problem by moving the runway exits in the .BGL. The two Tornados take the 2nd exit...the four F104's the 1st...all with minimal time spent on the runway. All now land in sequence...with no G/A. A word of warning to anyone trying this (just in case they don't know) If the .BGL has, like this Rimini, scenery objects built in, any changes using AFCAD will cause you to lose the scenery objects. I first renamed the LIPR.bgl to AF2_LIPR.bgl Then made the changes with the payware AFX (Airport Facilitator X ) After making a change, I then forgot, and opened it with AFCAD and made a further change. All the scenery was gone. I had to start from scratch again..so...only use AFX.

Russell.

Col7777 · Post by **Col7777** » 27 Dec 2008, 13:10

Do they land at roughly the same spot, if so change the afcad so it has one or two exits close to that spot, then they will be off the runway fairly quick.