freakingfast

My Feedback: (3)

Is it worth the effort to clip the wings to gain speed?
I just got anther World Models P-51 Rockwell Yellow. I had one years ago with a YS 91 in it, the crystal went out in the receiver and that was the end of that. This time the engine that’s going in her is an OS 55 AX with Macs tuned “Quiet Pipe”. I plan on racing it at SAMS in “bronze” and with the engine displacement I’ve chosen the rules allow me to reduce the wings area from 585 sq. in. to 513 sq. in. Basically it’s clipping about 3” off each wing tip. My thinking is, what speed I gain in the straits, I would scrub off in the turns due to the higher wing loading 25.8 oz./sq. ft vs. 29 oz/sq. ft. I know it would land hotter, but that’s not a deciding factor for me. Ideas ?

MustangAce

My Feedback: (3)

Sell it and buy the Dago Red.

freakingfast

My Feedback: (3)

The Dago has a fiberglass fuselage (heavier) and is getting eaten after the turns. I’ve been warned/told by several racers not to get it.
I was our field today and the local, many time gold class winner happened to be there and he said "Leave it stock, It would be faster clipped but it turns better with the full wing and less chance of hurting it at landing so you can still fly the next heat." Makes sense.

DonStegall

My Feedback: (1)

I would not clip the wingtips. You will get higher drag in the turns. Plus the wing loading is already pretty high on that plane. The Dago Red is even higher. I love mine with the YS 63 FZ, but it is heavier than the balsa fuselage P-51's.

I highly recommend you change the control horns on the retracts. Use the [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD947&P=7]Dubro Horn Bracket 4-40 3/32" [/link]

freakingfast

My Feedback: (3)

Thanks Don

Jimmy Skids

My Feedback: (2)

For Bronze and Silver don't clip. For Gold you may want to clip, but with a .55 AX you won't want to reduce the wing area. I've flown the clipped (one bay taken out) and unclipped versions and the differences that I have found are:

Clipped, faster roll rate, but reduced low speed handling.

Non-Clipped, better tracking and slow speed handling.

Unless you're really moving, the standard wing is the only way to go in my opinion.

Boy I love race season and all the planning that leads up to it. Freakingfast, if you decide on a clipped version I've got one you may be interested in with a YS110FZ. It was set up for gold but for the last couple of years I've won the Gold class flying the Spitfire's and I'm leaning that way for this years races as well.

Jimmy Skids

Tony Pacini

I wouldn't clip it for the Gold class, either; powered by a YS 1.10 the standard wing will break out of Gold (1:30).

They don't land the best, anyway (especially with a 1.10 in the nose), and clipping the wings would make it worse. What little speed you may gain in the straights will quickly be scrubbed off in the turns.

freakingfast

My Feedback: (3)

Thanks guys! I've glassed the center section all around and the saddle area on top. Carbon .007 x 3/16" wide strips were added to both sides, leading and trailing edges of the stab and recovered. Dripped in thin CA and chased it with thick on the inside of the fuse mainly the firewall, and wing hanger areas. The LG mounting area got the same. It used up 2 1/2 oz, of CA! LOL. Soon it will be in the air!

MustangRay

My Feedback: (7)

I bought a WM P-51 he assembled and he didn't do a good job! I put a Rossi 60 I had laying around on it. So do you think I need the fiberglass reinforcement on the wing center section? Is the stock hardware good enough for stresses it will go through? I haven't flown it yet so I'm making sure I get more than one flight on it ya know? Any good tips are appreciated!Ray.

Jimmy Skids

My Feedback: (2)

MustangRay,
With all due respect I sure hope that you weren't referring to me with your comment above, it sure seems like you were commenting on one of my builds by the comment. I've only sold one Mustang and it wasn't to you. Can you please clairfy whom you are referring to in the future when making this type of comment.
Thanks,
Skids

jeffk464

I think its always better to add a bigger engine then it is to clip the wings.

freakingfast

My Feedback: (3)

At the factory, they sanded the bottom of my wings so they match this also made the skin very thin were the two wing halves glue together. The skin (sheeting) carries a great deal of wing loading in the turns not just the main spar. Mine would have failed in a hard turn for sure. Iv'e seen and heard two wings fail this way. Sounds like a cherry bomb going off, than you see two wing fluttering down and the fuselage making like a lawn dart [:@]

As for the hardware it's mostly good if it's used in the right way. In the linkage, don't use the supplied "straper" for contol sufaces, get a "Z" bend tool and practice. Don't use the easy "linkage connector" for control surfaces and if you use them for retract, grind a small flat on the rod where the setscrew seats, use CA on the knerled nut and blue loctite on the set screws. I replaced the fuel tube keepers with large size fuel tubing it's less likely to split on the clevis. Some guys don't like the control horns because they have seen them break. I've looked over several crashes on planes that have used these horns and they were about the only thing still intact. Perhaps bad a mold/plastic in the past?

The engine mounts are great, I just don't use the two nose wheel plates(spacers). Be sure to shorten the fire wall screws so they don't poke a hole in the fuel tank if you do this.