Small Flying Arts

The 4 strand 1/8 motor still seems to be a bit anemic, although it works perfectly with my similar size/weight (Sterling) Mustang. It has quite a bit of washout, but too much decalage so a bit of surgery is needed. I have to also re-check the lateral balance.

The trick with a Spitfire, or any rubber powered model with pointed wing tips, is getting the transition from powered flight to glide right. It's easy to trim it to glide and easy to trim it for powered flight, however, the transition can result in a tip stall with a resulting spin. This one, with slightly clipped tips, should not be quite so sensitive. Hope you have enough washout in it. :?:

KF

Within the last 3 weeks, I've finally had the Spit out for some test flights. I really messed up the first day by installing the wrong motor - a braided (and TIRED) 4-strand 3/32nd x 16" instead of the proper, like sized, 1/8th. Needless to say, the model did NOT do much of anything :oops: !

About a week later, the weather again presented its nicer side so the Spitty again joined my SAAB for anther outing - with the correct motor :roll: ... but... after two "attempts" with about 750 turns (theoretic max of 1350),
1:- the model stalls under power but glide is so-so.
2:- the model is VERY critical about launch attitude - must be released with wing banked no more than 10°
3:- prop shaft was one with the "standard" commercial round hook causing the Gray loop on the rubber to flop over and creating severe vibration
4:- stretching motor for a third attempt revealed severe nicks - aborted

The motor was one that I have used in my Cloud Tramp (the year before last :roll: ) with at least 10 near full turns...

I've since made up a new motor, replaced the prop shaft with a reverse "S" hook, and the back-yard test today proved the worthiness of the design - Grey loop stayed centered and no vibration.

Thanks Robert! Believe it or not, the spinner is the supplied vacuumed formed one. I jus tried extra hard to get it mounted well :) .

I have done hardly any modeling for the past 2 years due to various reasons, many family related (good), but one really negative issue has been the lack of any interest by my club to even attempt to get an indoor flying opportunity - even tho there are around ten members who are interested (9 are for rc, one FF). another has been the excessive weather we've had - either too HOT, too wet, or too windy or a combination of the conditions.

We are presently in a semi-lockdown due to the pandemic making our field essentially closed. Hopefully all here have been spared.

So clean build! Very nice model, beautiful spinner!

A big brush fire in the area where I do most of my Free Flight flying and testing has put a "hold" on further activity. Normal rc flying is not affected tho the fire nearly reached the parking area, so I am not totally restricted :| . SEVEN tank trucks were involved in the containment which lasted nearly 5 hours and the private "garden" that also harbors a six hive bee colony seemed to be the ignition point (the hives/bees survived). 10,000 sq. meters was scorched to the dirt, but the danged blackberry thicket wasn't touched :twisted: .

My earlier plan was to make up the radiators from balsa - the plastic ones are >1.2gm apiece - but the weight savings came at an unacceptable loss of robustness and those that I deemed "robust enough" saved only 0.1 gram raw. The beast does use the protuberances to land on, so I did end up going for the plastic. Remaining to do - cockpit, pilot, canopy and exhaust stacks - and, of course, paint.

Another small test hop with 250 stretch-wound turns on the 4 x 3/32 motor (at the flying patch this morning) scared the bejesus out of me! Gradual climbing right turn with only a slight bank up to about 30 feet, then straight as an arrow toward the dreaded Blackberry bush (landed thankfully 10 feet short)! There was no sign of tip stall or any other problems typical of the breed - and it [u]was[/u] a bit breezy.

Weight for today's "fright" - 60 grams (no canopy). A bit heavy, but there is a LOT of wing...

Trying to test glide a model Spitfire is a comedy of errors - there's just NO way to get a good grip on the thing in the proper place :-?. Popped the spinner loose trying >:(.

Decided to heck with power-off gliding and stuffed a four-strand 3/32nd five gram (braided) motor in it and hand wound 100 turns so that it would have a bit of pull on release. Worked a charm :)!

Plane made it 3/4 of the way across the long axis of the yard, and even tho it was fairly turbulent, landed safely with the port wing slightly low. Also exhibits a slight left turn tendency - have to re-check the lateral balance.

Then came a heavy shower...

I was really surprised, myself, how the covering came out! Not to pat myself on the back, but it is the best tissue job I've EVER done - not perfect (there is on teeny-tiny wrinkle just forward of the starboard stab on the stringer and I could have done a better job sanding in a few areas), but more than satisfactory.

About an hour and a half after the above post, the wind died down to a breath so I made another couple of test glides. The first showed a definite tail-heaviness so another bit of lead was added in the spinner. Did the trick as the beast sailed across the yard and smacked into the wall after loosing only about a foot of altitude (same launch technique as the windy test). No damage other than the taped on spinner popping off and an 80BpM heart rate increase.

Now working on getting the prop/spinner mounting sorted and trying to find some detailed cockpit photos of the plane. Whether I do anything in there remains to be seen...

That is beautiful, excellent covering! And seems to be a good flier too, not many Spitfires would climb without engine power :-)