I just received a World Models Super Frontier Senior an ready to assemble it. However I noticed that the firewall has no right thrust at all,,,,Is it necessary to have any thrust angle? If I need it how much do I need? The wall is squared up and down , left and right. Im going to convert it into a tail-dragger with an OS 55. How will it fly without any thrust angle?


Thanks in advance for your comeback=====TAZZZZ[sm=confused.gif][sm=confused.gif][sm=confused.gif][sm=confused.gif]

If it's not built in nor say anything in instructions I would not worry about it. Just be conscious of a possible lefy turn in initial flight.Or call manufacterer.

Adding washers between the firewall and mount is pretty easy. You can adjust side and up/down thrust simply.

A lot of planes after much testing by the manufacture are determined not to require any thrust angle. After flight testing you may decide it needs some so then you can add washers. After you get it set the way you like then make a shim from hardwood and replace the washers. Usually the manufacture knows what works for there planes but it's still the pilots choice.

Some manufactures come with the firewall angled for better flight performance from the result of rigorous testing. There is a certain amount of left/down thrust on some models so it will improve handling. Depending on some models, adjusting the angles is not a wise choice. If I were to add washers to adjust the angle of the engine on one of the ARF planes I'm building now, the crank and cowl wouldn't line up.

It seems that every 2 weeks someone brings up this same topic.


Pete

There's also that situation where the firewall "appears" angled to the fuse but that's not necessarily the planes "thrust line".

As Gene suggested.

Fit it with an engine, fly it, then figure if you need any adjustments.

if it's got a vertical fin (that isn't offset) and a propeller... it'll need right thrust.<div>Start with 3deg.</div><div>
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How much is 3 degrees How thick a shim?

There is no magic number that tells you how much thrust angle is needed in an engine. Some plans and instructions will state a thrust angle for you or they will have the fire wall already set for that angle. They have done that after testing proto types of that plane and done all the thinking for you. I have five planes in flying condition in my shop right now, not one of them has an off set fire wall. Setting thrust is a big part of the trimming process of a plane during the flight testing. The design of the plane itself has a lot to do with how the P-Factor effects them, some planes are not effected at all or enough to notice. If you or your instructor doesn't know how to trim a plane then you can find a how to sheet from the AMA site or you may find one here in the pattern forum. Throwing in thrust on a new plane without knowing how it fly's first can run into a big problem before you ever get it off the ground. It helps a lot to have someone close to show you how to set up a plane. You may want to search out someone at a local club to help you. If you can find someone that has been involved in pattern flying that would be the person to ask for hands on help. If there is no one like that I can post you up a how to with photos so you at least have an idea. It sounds like someone once mentioned thrust to you and you have fixated on it. Correct thrust angles are a big deal but only after a point in time when you really start learning how to trim for flight.

Don't read into the instructions...if it doesn't say anything about an off set don't put one in......

Thanx you sir,,,Ill go along with that info. Ill leave as is and see what happens,,,if needed Ill add some if necessary.


Thaanks again-TAZZZZ[8D]

Do you have a computer radio? Throttle to rudder mix beats the crap out of right thrust. The amount of right thrust you need varies by throttle/speed. Notice you may need to counter the thrust on take-off, but not on landing. Thus, right rudder mix needed for higher throttle settings.

Do a search for RC Trimming charts. There you can find out how to determine how much right thrust or rudder mix you really need. Basically fly directly away from you with no wind, pull to vertical and set straight line, then let go of rudder and see what happens. If plane pulls significantly, you need an adjustment. There's probably another technique or two mentioned there as well.

Personally I think having no built-in thrust is a blessing.