CARS II

My Feedback: (7)

Flight report, mmmmmmmmmm none.
It will not get off the runway the wheels were to soft and they created to much drag and it couldn't get enough speed to rotate, I try 5 or 6 times but no joy.
All systems are go now that I have the new wheels maiden flight # 2 will be on Sunday PM, I got to work Sat.and Sun.

'Till then.

CARS II

Dash7ATP

For what it's worth, if it still won't rotate.........consider that the mains might be too far to the rear, and the elevator doesn't have the authority to raise the nose. I had that problem on a model of a Top Gun f-15 once. That model had a great reputation as a grass field model. It wouldn't even take off from asphalt! A friend noticed the mains were bent to the rear pretty far. We bent them back forward, and the next attempt was a very normal takeoff.

Good luck.,

Joe[8D]

joeflyer

My Feedback: (48)

Make sure that you have a slight nose up attitude as it sits on the runway or it will never get off. Measure the height of the center of the wing LE at the fuse. It needs to be higher than the center of the TE. I'd recommend at least 1/2", mine is 1" higher. The new wheels should help, make sure that they rotate freely.

Another problem might be a too far forward CG. Did you set the CG with tanks empty? From your pictures the fuel tank is forward of the CG, and 32 oz. of fuel adds a lot of weight. Even if that is not your rotation problem, in flight you will notice the change in trim. You might want to readjust the CG with 1/2 tank of fuel. Another option might be to try a short first flight with the tank about 1/2 full.

Good luck,
Joe

CARS II

My Feedback: (7)

Dash, Joe thank you for the tips. I checked the distance from the gear to the CG. and it is 1 3/4 apart more or less what the plans is showing.
Now that I have time to think about the test flight I came to the conclusion that the fuel tank was to big, to much weight at front combined with the drag from the wheels was what prevented it from braking ground.

Joe I CG it with the fuel tank empty, I'll try the same way with the new small fuel tank.

I have change the fuel tank to 21 oz. and change the tires to the skylights ones ( much harder ).
The airplane seats with a nose up attitude much like Joeflyer recommends, I'll take some pictures of it on the ground at the field next time I go, today Sunday will not be the time for test flight # 2 no time I'll have to wait 'till Friday.

'Till then.

CARS II

CARS II

My Feedback: (7)

Hey guys the maiden flight has been completed.

TO. speed was much greater than the last time, rotation came soon after it picked enough speed about half way down the runway on the climb out it wanted to go to the left and down, the engine response was good, it soon gain altitude and I began to trim it, after that it was sweet as honey flying at full throttle all the time the CG. looks OK. for now, loops are good high roll rate is fast on landing it could be coming very fast but as soon as you bring the nose up it slows down fast but it will fly very very slow.
Three flights all together at seven minutes at full throttle it will burn about 5 oz., throttle response at idle is good an over all wight of 12# dry.

The only real concern that I have is that the engine is not turning the fan more than 17K, I have a Ramtech/82 K&B.

Pictures to come latter..


CARS II

Dave03B

nice 1[sm=thumbup.gif]

CARS II

My Feedback: (7)

Thank you. Dave.

CARS II

CARS II

My Feedback: (7)

Hey guys, here are the pictures at the field. The K&B 82 is not working out as good as I thought, I have repalced it with my new OS 91, I will test fly again this afternoon .

CARS II

Dave03B

oh, you'll just have to 'make do' with the OS91.

dont suppose anyone can post a flight video of their enforcer?? after all the talk, i need to see the action

CARS II

My Feedback: (7)

Looking inside. The BVM remote needle valve is about 15". away from the carburator, it is recomended to go no farther then 9", and I'm using pipe pressure so far it is working good with a good throttle responce.

CARS II

Dash7ATP

HI Cars,

You may find the the .91 still won't give you the performance you expected. I'm thinking the reason is the open intake and exhasuts on the Dyna-Max fan. If you remember, several of us mentioned that a good percentage of the Dyna-Max preformance is predicated on good smooth entrance and exhaust flows. A rounded lip going into the fan will probably make a big differance. You will also get more speed if you can put an exhaust duct on it to reduce the outlet diameter down the the swept area of the fan or even slightly less, maybe 10%. To arrive at that, you take the area of the shroud inside diameter and subtract the area of the center fairing. The squared off back of the engine mount creates a LOT of drag!

Let us know how it does on the ).S. .91

Joe

CARS II

My Feedback: (7)

Thanks Dash, I do remember and I had it in mind as I keep building, don't get me wrong about the performance I knew that it will have some limitations I flew others airplanes like this and I knew where I was going with this project, so far it has been nothing but fun on the last part of this project, the reason for the low performance of the K&B 82 is that it is only turning the Ramtech fan up to 17K, my K&B 7.5/Turbax was giving me better performance than this I know that the OS 91 will give me the punch that I need, I will add an exhaust tube some time after the 10th flight because I want more speed.

To day I talked to Tom Cook from JMP and he helped clarified some issues regarding the OS 91.


CARS II

CARS II

My Feedback: (7)

Last report. In a few words it flew just fine, very reliable fuel system and engine.

I'm happy with the way it is and the guys at the field think that she is hot.

Thank you to you all for the comments and help.

CARS II

ahdflyer

Wow, this is a long thread.
To the "kit bashers" of the Enforcer; I am currently constructing a F22 based on the Enforcer wing planform. Has anyone added tail feathers (extended elevator) to the Enforcer? How did that work out with regard to center of gravity?

CARS II

My Feedback: (7)

Go to kit building they may have an answer regarding the change of CG.


CARS II

Daryl Martel

My Feedback: (3)

I thought some of you Enforcer fans might find this interesting. I've got the kit in a box on my "to do" list for this winter and have an S.T. 90 set aside for the project. I modified the stock muffler and a Dubro Arise quiet muffler to fit. It's got just the right amount of prop clearance exhausting straight back through the prop arc. Hopefully it'll provide just the right amount of back pressure, lower the noise to an acceptable level while still producing good performance. I'm looking forward to the build - I'm a big fan of deltas. Cheers

peter b-RCU

My Feedback: (119)

please help on the retracts i that i need on my enforcer with byro-blast, spring air or robart and why and also the part number or model of retracts, thanks in advance

peter

[email protected]

Dash7ATP

Peter,

I don't think it will make much difference which brand name you use for your retracts. The only advantage I can see with SpringAirs it the simplified plumbing. The spring down feature is not always a plus, as any binding in the system might be enough to hold the gear up. At least with Robarts, etc, you will have air pressure to assist with gear down. Of course, if you loose air pressure, the Spring Airs will extend, where robarts might not.
Be sure you get a heavy duty set that will support a 3/16 wire gear or the Robart 3/8 struts. The small size wire will bend and cause problems in the gear well clearance.

Good luck on your ByroBlaster. You will like it.

Joe

livinabox

Hi gang, its been some time but i flew the enforcer today on a super tiger 61 and have to say i was real dissapointed.
Slow or what.....id sooner watch a skip rust!!

My lazer arrow on a 46 would leave it for dust.

its up for sale.

Strykaas

Put a real speed engine on this !

joeflyer

My Feedback: (48)

Just about done with my second Enforcer. This one is powered by a Ram 500 turbine. I hope to do the maiden flight in a week or two. My DF Enforcer will do 140-150 mph, the turbine one should be a real rocket.

Joe

Strykaas

Now we're talking

livinabox

i would have if i could get the right prop for it ....pushers are hard to get in the size ya want.
Any way what engine would you sugest? Iv already bought a jet 50 for another plane and that
was awsome .....but the price....jees!!!

Strykaas

Move on to a .91 !!

Jett .90, Mvvs .91, OS .91, etc... cheap and expensive routes, make up your mind

Many today's .91s use the same case as .61s, so ...

Bill Yonescu

My Feedback: (44)

Just an update & clarification...

I sold my Enforcer without the Tower .75. I bench tested the engine and found out that a 11x7P APC is not the same as a regular 11x7 APC. My Tower .75 repeated the same RPM with a 12x6 puller (12,600) but turned 13500 rpm with a regular 11x7. With the pusher version it turned 14,700. Most-likely, the pitch is different but possibly the "shadow" of the engine and plane cause this difference.

Anyone else notice a large difference in the pusher vs. the regular puller configuration ??

Bill