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Joined: 11/30/2003 From: Cadillac,
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I am allowing myself to hope that true summer weather has finally arrived in northern Michigan, US of A. We have had two days in a row where the wind waited until around 3pm to start blowing 25-30 mph.
I took the Arrow down to the lake this AM, but the water was still all riled up by the winds of last evening.
Maybe tomorrow. Hard to say, but I want calm water so I can learn how to get this bird up on plane without flipping it.
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Joined: 11/30/2003 From: Cadillac,
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I love the way this airplane flies. I just can't believe how smooth and stable it is.
This morning the wind was clam, and the lake was almost flat, just a slight ripple leftover from yesterday's howling gale. Because of that, the left turn during taxi was noticeable. It required a few beeps of right rudder trim (about 1/8" measured at the TE of rudder) to correct, and away we went. (I had lots of trouble getting the lower fin, the pod, the engine and the upper fin to all line up.) I just slowly advanced the throttle, there was no tendency for either wing to dip, and she was hauling off in a level, planing attitude after about 50 feet. I fed in some more throttle until she started to get far away from me, hauled back on the stick, and away she went like a homesick angel.
I only flew around in circles to get the trim (it required about half the available up trim, 50% according to the radio, in addition to one clevis turn of reflex up I had put in earlier.) and I really like the way it cruises around at about 1/3-1/2 throttle.
As you can see, I blew the landing completely. I didn't slow her down enough like Laddie describes, bounced real high off the water, tried to go around, and the throttle being snapped open at low speeds resulted in a nose dive into the water from about 25 feet altitude. The damage was very light. The left wing has #2 (balsa) rib cracked and the center section sheeting popped away from the LE sheeting. The forward left mounting box separated a tiny bit from the extreme end. I'm going to let the hot lamp cook the moisture out of both places, then do some epoxy/milled glass and covering/paint work, and she'll make the club float fly tomorrow.
I used a 10 oz fuel tank, and the EMPTY CG was 16" (408mm) forward of the wing TE (not counting elevon), measuring right along the upper surface of the wing with a tape measure, and she hangs just slightly nose low on the balance rig, upside down. This was per Simon's data on the original build thread.
Control throws are exactly as Laddie states in the build article, with expos at -35 aileron, -45 elevator & -80 rudder. I don't use dual rates because I know I would forget to flip the bloody switch at the most inopportune moment.
By the way, the OS 55AX appears to be a perfect engine choice for this design. With the 11x7 3 blade MAS prop, there is plenty of punch, all the speed I would want, and no prop clearance issues.
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Joined: 5/2/2007 From: Salinas,
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Congrats Bob on a successful build and flight. The plane looks great. I am in the late stages of a Northstar build and this thread makes me want to build an arrow next.
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Thanks, Yak. Go for it. You'll love it, although I saw a Northstar at a float fly last year and I have to say it flew every bit as good as my Arrow does.
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Joined: 3/21/2003 From: Paris, FRANCE Status: offline
Bob, may your continued efforts and dedication be an inspiration for other modellers. I'm really happy you've made it, in this "plug and play" world ... MANY would have given up in your situation.
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Thanks, Strykaas. I have plans for this general design, ie, delta wing, engine mounted high on the tail. What do you think about an F-106 in this configuration? No prop clearance issues or balance issues like prop-in-the-nose pretend jets. No costly DFs, EDFs, or turbines.
Knife edge yak: when you are posting, click on the "click here to upload images and files" at the lower left of the response box. It will take you to a little menu where you can find the photo you wish to post, which must be saved in your data base.
I have plans for this general design, ie, delta wing, engine mounted high on the tail. What do you think about an F-106 in this configuration?
Well, it could be nice indeed, strange but nice . I think it hasn't been done before . I would double check if it is compatible with a correct cg location though. I guess it is with such a long nose.
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Joined: 11/30/2003 From: Cadillac,
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I think that long nose would allow a fairly heavy engine to be balanced. Here's the specs I had in mind, which meet the IMAA jet/ducted fan rules:
F-106 Delta Dart Michigan Six Pack, 191st Fighter Interceptor Group Wingspan: 51" OAL: 90.27" WA: 820 square inches (approx) Power: .91 2 stroke Prop: 13x8 2 blade Engine location: pod mounted on vertical fin, tractor configuration, fuel tank in pod Main Wheels: 3.5" Nose Wheel: 1.75" 20" of nose to be removable for transport, wings removable for transport. (Ala Arrow design) Robart spring down retracts, strut ready Bob Violett air brakes. Deployable drag chute Target weight less fuel: 9 lbs. Target wing loading: 25 oz/square foot
The problem with the 106, is that the sweep angle on the vertical fin is somewhat shallow. That means the engine would have to be WAY out in front of it to get prop clearance. I'd probably have to build a support tower that originates near the forward, lower fin and is out in front of the fin in order to support the firewall properly. Maybe I could paint it so that it would not be very visible in flight. Maybe the same color for the engine pod.
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Joined: 5/2/2007 From: Salinas,
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I know this is an arrow thread but you guys seem to appciate all things Laddie so here is my Northstar build. I am building the canopy and what a pain it is.
< Message edited by knifeedgeyak -- 6/25/2008 3:16:17 PM >
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All Forums >> RC Airplanes >> Seaplanes >> RE: Laddie M's Arrow - 2nd Attempt 
RE: Laddie M's Arrow - 2nd Attempt - 
. I think it hasn't been done before 
. I would double check if it is compatible with a correct cg location though. I guess it is with such a long nose.
