Old Design, Updated -- Angel Express Mk II

[CPMcGraw]

This is another of JP's great artworks, from May of 2006. I don't know if this was ever posted (I think it was, but only as experimental), but the design was a challenge to work up. Even in RS9, with the PODS feature, it was tedious to create all of the truss members. RS9 did simplify the task, there was just so many of them...

I did make a couple of alterations, concerning the placement of launch lugs and the way the ringtail attaches to the truss. I eliminated the ringtail's pylons and have it attach through the truss frame. Since each set of truss pieces attaches to the main body tube in so many places, I figured the entire structure would be sufficient to take the launch loads.

Recovery is via 20" parachute, which gives it a gentle 8 FPS descent rate. All launches on the engines listed reach safe flight V in 36", but I used 3/16" launch lugs in case someone wants to put an engine in it that needs 48". The acceleration off the pad is soft, relatively speaking, with all three engines listed below.

Length: 34.89"
Diameter: 1.566" (PPB)
Fin Span: 2.79" (ringtail)
Weight: 1.8 oz


D12-3........494'......Dv 8 FPS
D15-4T.......518'......Dv 23 FPS
E6-2........1233'......Dv 18 FPS


It's a shame this design needed RS9 to get right. James had a great design here and we couldn't prove it short of building it and flying it!

Enjoy!

[rstaff3]

Tell me this thing has actually flown. Very interesting indeed.

[CPMcGraw]

James will have to tell us if he built one. I'm under the (working) impression it was only a simulation flight. RockSim has fooled us before with ringtail designs, saying they were stable only to find the calculations were really bogus.

My personal feeling is, it needs some additional fin area... :(

[James Pierson]

I finally got around to pulling this design out of the "Abby Normal" Rocksim folder and give it a needed workover with R9. The original file was unstable in R8. After reworking this design I realized that in order for an single 18mm to work it had to go on a severe diet. After conciderable wieght and drag loss, sorry Jay those Ping Pong Balls had to go, I have an design that still look somewhat like the original and yet preforms well on an single 18mm motor and I call it the Angel Express Mk III.

In order to keep this design in its more original form I needed more power and used an dual 18mm motor mount. Angel Express Mk IV also needed more length and more aft drag to be stable with the dual 18mm motors. Niether design has been built yet.

Enjoy and Thanks Again, JP

James Pierson
NAR# 77907

Angel Express Mk III (18mm)
Launch guide length: 36.0000 In

MOTOR.................MAX. ALTITUDE...........DEP. VELOCITY
A8-3..................150.36647 Ft.............15.7435 ft/s
B4-4..................355.03281 Ft.............13.4529 ft/s
B6-4..................361.15814 Ft..............9.6000 ft/s
C6-5..................771.48622 Ft.............14.7453 ft/s


Angel Express Mk IV Dual (18mm)
Launch guide length: 48.0000 In

MOTOR.................MAX. ALTITUDE...........DEP. VELOCITY
2-A8-3..................162.89862 Ft.............11.7067 ft
2-B4-4..................380.62336 Ft...............9.4061 ft/s
2-B6-4..................386.00394 Ft..............6.0777 ft/s
2-C6-5..................811.46982 Ft.............12.5614 ft/s

.

[CPMcGraw]

Looks good, James. I've just posted them to the Master List here in the Forum and on the Blogsite. For encouragement, we only need 68 more designs to make 700! :D

[James Pierson]

Looks good, James. I've just posted them to the Master List here in the Forum and on the Blogsite. For encouragement, we only need 68 more designs to make 700! :D


For Encouragemant Craig, :D ;)

Besides you know my first love of the "Test Flight" :cool: , JP.

BUILT Pile:

Sky Jack
Sky Marshall
Heeby Jeeby
Space Cruiser Pacifica
Sky Champ 13mm
Sky Champ Paper Transition 18mm
Sky Champ Balsa Transition 18mm
Flying Flea
Shadowfeet Interceptor
Lighthawk Interceptor
Galactic Goblin

Test Flights Pending!!!

James Pierson
NAR# 77907
.

[mycrofte]

I was thinking of one similar to that. Thought I would paint it brown and put UPS logos on the fins with EXPRESS CARGO down the side...