A pair of Douglas rocket aircraft in profile: Skyrocket and Skyflash

Was looking around for interesting rocket aircraft to do in profile Depron that Frank has not done yet...

I had recently read the book, "Ed Heinemann, Combat Aircraft Designer."

Part of the book involved the design and engineering of all three (including the jet powered Skystreak) experimental D-558 aircraft. Decided to do profile versions of the Douglas D-558-II Skyrocket and the never built Douglas D-558-III Skyflash.

A couple of other models were on the bench ahead of these, but I decided to press ahead with this pair for now .

The following three views were tile printed to give overall lengths of around 38-39". All major parts are now cut out and some of the Skyflash parts have been bonded together.


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And here are the "kits" cut out of 6mm Depron.

The Skyflash is going to be a hot rod on the E6, I think. Next parts up for it will be the flying stab pivot assembly. Not a lot of finish work on it... A couple of stars and bars on the fuse, some small tail markings and the Douglas Skyflash logo on the forward fuse. Get out the Sharpie and add a few panel lines.

The Skyrocket will need some carbon in the vertical tail to support the high mounted horizontal tail. Finish is also very simple, much like the Skyflash.

More as they develop.

Those look good tom, I think they'll be great flyers. For the tail support I've done carbon, thin styrene sheet laminated on both sides up to the horizontal stab, and just doubled the fuse top, all worked about the same, the doubled fuse looked better to me especially in a white model and allowed me to round the body more for 3d effect. Thus is for vertical stiffness to prevent twist, or were you meaning horizontal carbon for the horiz tail support..?

Frank

Made some progress on my pair of Douglas rocket aircraft while off work over the holidays. Not far from being ready to fly.

The D-558-III Skyflash is ready for the motor mount, the radio installation and a couple of other minor odds and ends of decoration and hardware and will be ready to fly soon.

The D-558-II Skyrocket is ready for control surface hinging and radio gear and the same minor odds and ends as above.

Still have to draw up the Douglas logos for the two aircraft and get the vinyl cut. They might get flown before I get around to that little graphics job.

Found a decal sheet for small scale D-558-II and D-558-III plastic models and have it on the way to be scanned to create the art the Skyrocket and Skyflash logos. These all white aircraft really need some markings to make them interesting!

Just about done with both models otherwise. Will post the completion pics after the logos are added. If I don't get a chance to test fly at the local RC field, will try to get the first flights in at the DARS launch on Jan 16 or perhaps Jan 30.

Flew the D-558-III Skyflash for the first time at the HP launch in Asa today.

Needed just a touch of up trim on the boost... Likely needed due to the heavy bits like the servos and battery being below the fuse centerline. Flew so well on the boost that I rolled it twice on the up line just before burnout. Excellent boost altitude, as it is fairly small and light.

Glide wise, it flies a lot like Franks X-15: stable and nicely controllable, but definitely searching for the ground...

Sorry, no flight photos. I have the worst luck getting someone to take photos while I am flying. Going to have to greak down and make a hat cam for some video.

Will post some photos of the fully completed model.

Congrats Tom, looking forward to seeing it all done up.

At long last, here are some flight photos of the Douglas D-558-III Skyflash, This is the second flight of the model and the photos were taken at Naram during the sport launch on Saturday.

I actually used a very elderly E6 reload on this flight. It was purchased in a batch of stuff from an estate and was at least 20 years old, and no data exists on how it was stored. It was still sealed in the original bag and was still airtight. The propellant was noticeably dryer and harder than a fresh reload, Decided to try it, anyway. i did slightly abrade the slot in the propellant slug to help expose fresher layers of the fuel.

Ignition was instant and normal, but the motor seemed noticeably down on thrust, perhaps 15-20% or so, both during the thrust spike off the rod and during the rest of the boost. It also seemed to tail off early. Still was a very decent flight on this fairly light model. When I cleaned the case, There was an interesting white deposit on the inside of the nozzle, near the hole. Popped it off and it was hard like a large salt crystal. Some chemical migration must have taken place inside the propellant slug during the the 20 year storage period.

Rarely for Richard, he missed the boost phase and most of the pics are of the Skyflash gliding.

The D-558-II Skyrocket model is resting at 90% complete and WILL get flown sometime this year.

tab28682 said:

The D-558-II Skyrocket model is resting at 90% complete and WILL get flown sometime this year.

Click to expand...

Only a few more days left in the year... Did it ever fly?