Rockets using PNC-60AH cone

[jetra2]

Hi all,

I recently picked up four PNC-60AH nose cones from the local hobby shop. I needed one to finish my Strap-On Booster's project (hope to debut it next month) so now I have three PNC-60AH's, and no rockets to use them in. The obvious rockets are out of the question, the Der Red Max and the Citation Patriot...those are overdone, and Eugene's cloned those already.

So, I guess what I'm asking for is rocket plans or upscales of other rockets that would end up using the PNC-60AH.

Thanks!

Jason

 

[SecretSquirrel]

Scratch built Screamin' Mimi??

 

[flying_silverad]

Hmmm........Omega!

 

[sandman]

Estes Mean Machine, Hawk, an Upscale Goblin, Space Cruiser Excalibur, Long John Silver, Der Red Max, Der Big Red Max, S.W.A.T.

That is a very popular nose cone!

sandman

 

[Fore Check]

Add these to the list:

Army Hawk (#2031)
Arrow (#0881)
Maxi-Icarus (#1331)
Renegade (#1271)

That ought to just about cover it with those mentioned above. As far as current kits, add the Blue Ninja.

It's not clear in the plans; does the Super Vega use a 60AH or is it different? Hard to tell; although the cone that comes with the SV comes with a nozzle too, and I'm not aware of any 60AH/nozzle combos. Probably means it's different.

 

[jetra2]

Well...I've narrowed it down to the Space Cruiser Excalibur and the Omega. I've got rings to build an Omega 24mm to 18mm, and I really really like the looks of the SCE! I think I will do the Omega first, so could someone post a V5 Rocksim file or the fin patterns and lengths of tubes?

Thanks!

Jason

 

[shinbone]

Here's a great reference for matching kits and cones:

https://www.rocketshoppe.com/info/Estes_Nose_Cone_Reference_lg.pdf

 

[sandman]

Jetra,

Be warned! On the Space Cruiser Excalibur, the rivet decals will drive you buggy!!

If you have a stigmatism yer in real trouble!

If ya do the Space Cruiser ya gotta do the Dragonship 7!

sandman

 

[Fore Check]

Nice reference chart, Shinbone! I'm suprised we hit most (well, all really) of that list without it!

Gosh, we really *are* geeks.

 

[astronboy]

How about an upscale Blue Bird Zero?

Here is the EMRR of mine:


https://www.rocketreviews.com/reviews/scratch/blue_bird_zero_bt60.html

Fred

 

[jetra2]

That might be a good way to use the third cone, Fred...I kinda like it!

Can someone please post the dimensions of the fins for the Omega? I'd really appreciate it! You see, I'm in this building mood right now, and I want to crank out as much stuff as possible, so if you would please do this...I'd be most thankful!!!

PLEASE!

Jason :kill:

 

[Fore Check]

Hey Jason,

JimZ's has the plans available. The fins are on the site in *.TIFF format. If you save the picture of the fins on your computer, and then open the file using the "Paint" program that comes with Windows (that cheap drawing program that is probably located under "accessories" within the "program files" in the start menu), it will open them to the correctly scaled size.

Here's the direct link to the fin template: https://www.dars.org/jimz/estes/k-52g.tif

Now, it may look huge and funny when you open the file on your screen, but if you print it without any "fit to page" or scaling options selected, you'll get correctly sized templates.

I know, it's cheap and dirty, but it works!

Hope this helps!

 

[jetra2]

Actually, it looks really small and blurry...might there be any way someone can print it to a PDF file and post it here in the correct size?

Thanks,
Jason

 

[Fore Check]

I'm pretty illiterate with Acrobat - don't know how to do what you're proposing.

However, see if you can draw them up using these dimensions.

For the Booster fins:

Root chord length: 3.625"
Tip cord length: 2.5"
Fin Span (distance from root chord to tip chord, perpendicular to airframe): 2.75"
Tip chord is parallel with root chord and "centered" to make a simple trapezoid.


For the Sustainer fins:

Root chord length: 3.125"
Tip chord length: 2"
Fin Span (distance from root chord to tip chord, perpendicular to airframe): 2.25"
Tip chord is parallel with root chord and "centered" to make a simple trapezoid.


If you tell me how to do what you're proposing regarding the PDF file, I'll try.

 

[jetra2]

Ok...thanks...I'm running it thru Rocksim now. Can you post the body tube lengths quickly?

EDIT: Can you post the sweep lengths of the fins?

Thanks,
Jason

 

[Fore Check]

Sorry for the delay - I ran out for lunch.

Anyway: The sweep lengths can be calculated using the Pythagorean Theorem more accurately than me measuring.

To wit:


For the booster fin:

SL^2 = ((RC - TC) / 2)^2 + FS^2

SL (sweep length) = 2.806938947



Same equation for sustainer.

SL (sweep length) = 2.319246914


Do you need the body tube lengths?

 

[jetra2]

HUH?! How the heck do you figure that? That's going to be one funny looking trapezoid, if that is in inches...

....maybe I oughta just design a nice two-stager...

Jason

 

[Fore Check]

Jason: My bad - by sweep length, I was thinking the length of the leading edge.

Sorry.

The right math to center the tip chord over the root chord is:

SL = (RC - TC) / 2


For the Booster, SL = 0.5625

For the Sustainer, SL = 0.5625

I forgot that part of the RockSim jargon - I usually use "free form layout."


BTW: I used the dimensions we've finally arrived at here and put them in on RSim to be sure, and they look right.

 

[jetra2]

Tube lengths?

I'm going to use this post over several edits to create my plans for this bird.

ESTES K-52 OMEGA DIMENSIONS
____________________
Sustainer:
PNC-60AH
Main BT-60 (length: 14")
Payload BT-60 (length 5")
Motor Tube BT-50H (length 7.75")
1/8" balsa fins:
Root Chord: 3.125"
Tip Chord: 2"
Fin Span: 2.25
Sweep Length 0.5625"

Booster:
Main BT-60 (length: 5")
Motor Tube BT-50H (length 4")
Stage Coupler
1/8" Balsa Fins:
Root Chord: 3.625"
Tip Chord: 2.5"
Fin Span: 2.75"
Sweep Length: .5625"
____________________

Thanks much, Simon, for your help! I'll likely start tonight on this project - I've got everything laid out and ready to rock(et).

Jason

 

[Fore Check]

Tube lengths:

The sustainer in the plans is built with a payload section and then the main airframe, coupled with a balsa nose block.

Payload tube = BT60R = 5.00"
Airframe tube = BT60AD = 14"
(Net airframe length, if built w/out payload section = 19.00")

Sustainer motor tube = BT50H = 7.75"

---

Booster airframe tube = BT60R = 5.00"
Booster motor tube = BT50S = 4.00"


---

As a note, I've had the discussion (with Astronboy, I believe) that there is a design flaw in the gap staging method used in the plans for the Omega. There are no vent holes in the upper end of the booster motor tube, nor any vent holes in the centering rings in the booster. I don't remember all the exact reasons, but I *do* remember that this is (at least) potentially bad - and the possibility of the booster popping away due to the pressure of the forward stage ignition gasses popping the booster off before the sustainer motor lights. I believe Fred cited Stine's discussion of gap staging in The Handbook of Model Rocketry for reference.

I haven't built the Omega, but I'm pretty familiar with the plans as I've been heavily contemplating it. Our discussion was regarding the differences that I noted in the gap staging design of the Omega (an assumed "proven design") and a different rocket.

Anyway, just food for thought.

 

[jetra2]

Originally posted by jflis
First, with respect to the Omega, note that it employed Pop-N-Go staging. Meaning that the two motors were *not* taped together. There was a gap (I can't remember how much) and both stages had engine hook retainers. Also, there were *no* vent holes cut.

This was posted a while back in a thread on staging by Jim Flis. The gap looks to be about one inch or so. I'm going to try it out with no vent holes first - see if that'll be super-horrible. I don't think it will...I might have done it before, I'm not sure.

Jason