Air Tractor Fire Boss

Boof69

Well-known member
12oclockhigh said:
I was thinking this because it was a bit hard to taxi into position. ??? Brake drag ???...
It is hard to taxi in to position but I think this is due to to the nature of turboprops. Spooling up the engine to spin up the prop. By time the prop is going the rpms are too high and your going to fast. Slow taxi is almost impossible. No brakes are applied on the swaps version.


Unless there is something I don't know about the brake setup in RF it seems as if I apply any useful amount of brakes a noticeable drag effect happens. This setup works fine with my YF-23 because of the high power to weight ratio. The engine just over powers the brakes, but with the Fire Boss the lower power of the turbo prop makes this drawback more noticeable. I would prefer a good braking setup but the drag takes away from the scale power feel I was going for. I settled on the lesser of the two evils.
 
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Junkboy999

New member
Help on taxi

I was wondering the same thing about the wheel breaks. I noticed I had to Rev the engine up to about 75 % for 3 seconds and then release the throttle and the plane with roll about 3 feet and them stop. To taxi I had to gun the throttle up and down and only roll when the throttle was down. I checked there are NO wheel break Physics set up on the model. I think this is do to the weight of the model and the why the engine is over the steering wheels. With the mains so far back and the steering wheels under the props I believe ( I might be wrong ) it is the down thrust being calculated that is adding to much friction to the castering nose wheels.

This helped a the taxing. You will still have to gun the throttle up and down a bit but it will roll better.

Look under Airframe / Floats / steering gear / steering wheel / (Setting call ) Friction Multiplier. Set this to 50 the lowest setting

bear in mind this works with the Airports set up ground friction “ Affects steering and braking friction for this wheel. This is combined with settings in the airport or runways to create the effective braking and steering friction available. “
This does make it roll a bit longer on landing.

If you set the mains to the same 50 setting it will taxi better but now you’ll need to install wheel brakes to get it to stop on paved runways.

I hope this helps.
 
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doug schluter

Well-known member
Unless there is something I don't know about the brake setup in RF it seems as if I apply any useful amount of brakes a noticeable drag effect happens. This setup works fine with my YF-23 because of the high power to weight ratio. The engine just over powers the brakes, but with the Fire Boss the lower power of the turbo prop makes this drawback more noticeable. I would prefer a good braking setup but the drag takes away from the scale power feel I was going for. I settled on the lesser of the two evils.



Boof69 check out the setup for Brakes on your excellent 802 , this is how to set up Brakes so as not to cause drag when no brakes are applied
 
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Boof69

Well-known member
Your right that works great. Would you post it then? Did you do engine mods too? Because that will erase the engine I made if people aren't careful during import. When I imported your .RFX it asked if I wanted to replace my AT-802a.
 
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jeffpn

Well-known member
That engine overwrite notice will occur whether the engine has been modified or not. Still need to be careful, though.
 

doug schluter

Well-known member
Boof and jeff your right about the engine just a slight mod i should have said not to over write it but i just wanted to show the brake setup and did not intend for others to use it Boof go ahead and do an AV up and i'll erase this AV .
 
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Junkboy999

New member
I gave it a try and found there I could add another channel to set up a break servo Like on some of my planes , but it would not let me select it. I guess 12 is the max.

If you just pick the pitch servo ( channel 2 ) for the break It will work but you the break is full off on stick full up and full on on stick full down. That is why I like to make my own channel. I like the make the break operate only on half of the stick movement.

I even set it up on the throttle so full power takes off the break and cutting the throttle apples the breaks, but it still does not work like adding a dedicated channel for breaks. Really not good AV material.

Shoot me an E-mail addy in a PM and I send you my A-10 (WIP) to see how I set up my Break. My speed breaks only add a small % of wheel breaking because I have ground spoilers that aplies a larger % of wheel breaks.
 

jeffpn

Well-known member
Boof69 said:
Sorry I don't post AVs of my models.
I've done that a couple of times.

You do have a workaround, should you ever need it, though. I know you'll pull an EA and repost it, if you find a mistake. I'd find it hard to believe that mistakes are limited to the 3D model or to the CS. An AV could have a mistake as well. I'm not suggesting that your physics in the Air Tractor has anything wrong with them, so long as you are happy with the model's performance. I'm just saying for future reference.
 

12oclockhigh

Well-known member
Boof... thanks for all your work, fine plane... thanks Doug ... too!

This all started because I wanted a nice close look at all the great graphics work you did... the plane is great.
 

doug schluter

Well-known member
ok i redid the Brakes addition to Boof's excellent 802 with no other changes put the AV on the swaps , i can't wait to see what he does next : )
 

Boof69

Well-known member
jeffpn said:
I've done that a couple of times.

You do have a workaround, should you ever need it, though. I know you'll pull an EA and repost it, if you find a mistake. I'd find it hard to believe that mistakes are limited to the 3D model or to the CS. An AV could have a mistake as well. I'm not suggesting that your physics in the Air Tractor has anything wrong with them, so long as you are happy with the model's performance. I'm just saying for future reference.
I know I can and have pulled an EA to fix something. On this model in fact, but IMO it flies, lands, and taxis to my satisfaction. Also Jim was satisfied before release. Brakes are a small matter for people to play with.
BTW did you try it out Jeff? What do you think about the brakes?
 

andy29847

Active member
Thanks for the psd files

Boof - I have wasted a whole day working on another color scheme for the airboss. My wife wishes I would cut the grass. :) I need to add a few more details before uploading. Thanks for the link to the psd files.
 

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Maj. Numbskully

Well-known member
andy29847 said:
I noticed that the prop was tiny in the recording - it looks fine when flying. Something is a little funky.
Sounds like you increased the Vehicle Graphics Scale ....
when doing so you must also go to the engine and increase the Prop Visual scale separately or your prop remains scaled to the original size

Not to mention the all to often overlooked changes that should be made to component wights, CG ,correct wing loading etc to get it to fly correctly at the new scale
 
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