42,305' - 98mm Minimum Diameter

[Burner]

Yesterday at the Friends of Amateur Rocketry site I reached a personal altitude record with my 98mm minimum diameter rocket on a research N2600 (~16,200N-s) to 42,305'.

Some stats:
-6:1 Fiberglass von Kármán cone
-Featherweight Raven2 (with perch), BRB RF beacon, BRB GPS (all in the nosecone)
-Primary and redundant apogee charges in surgical tubing
-Single 60" section of FWFG tube
-.093" fins with two layers of uni-directional carbon and one layer of plain weave
-Drougeless apogee with 84" main released via line cutter
-8 pounds empty, ~40 pounds loaded

Some construction shots:

This weekends flight, ignition.

Going up fast.

Time for some cotronics.

Raven Data.

 

[Adrian A]

Congratulations! I like your fins. It would be cool if you post the Raven data file to look at in more detail.

 

[patelldp]

Wow! That is awesome! Forget the Cotronics...time for aluminum...no more SU fincans!

 

[daveyfire]

Nicely done, sir! Awesome flight! How far away did it end up landing?

 

[bandman444]

AMAZING flight.

And thank you thank you thank you for letting us use your pad.

Here is the photo we got.

You dont happen to have any photos from our flight?

 

[edwinshap1]

It was truly an amazing flight. The roar off that pad (200-300ft?) was immense. Gotta love test bunkers

 

[thobin]

Is it just me or does carbon fiber just look totally awesome.

TA

 

[Burner]

Congratulations! I like your fins. It would be cool if you post the Raven data file to look at in more detail.

Thanks! I'll try to remember to grab it off my laptop later.

Wow! That is awesome! Forget the Cotronics...time for aluminum...no more SU fincans!

Seriously, the novelty of burning your fins off is very short lived. I have almost finished ripping off all the carbon to re-bag it. Not easy, sucks.

Nicely done, sir! Awesome flight! How far away did it end up landing?

Thanks! It was only 2.5 miles northeast of the site, luckily it was pretty close to the BLM service roads so I only had to walk a quarter mile and army crawl under one fence.

AMAZING flight.

And thank you thank you thank you for letting us use your pad.

Here is the photo we got.

You dont happen to have any photos from our flight?

You're welcome, didnt know you were a fellow TRF'er Love the picture, you can see the flame down the whole tower! Your flight was awesome too, got a shot of it here although my photog skills suck.
I had to leave before you guys got back, how high did it go?

 

[tfish]

James, Nice job. Now I have to push my 98mm.

Tony

 

[Burner]

James, Nice job. Now I have to push my 98mm.

Tony

Thanks Tony, not sure I could have pushed this one too much further! But I intend to try.

 

[bandman444]

You're welcome, didnt know you were a fellow TRF'er Love the picture, you can see the flame down the whole tower! Your flight was awesome too, got a shot of it here although my photog skills suck.
I had to leave before you guys got back, how high did it go?

It went 30,197' and landed only 1.6miles from your pad. We even and the main come out at apogee! Talk about no wind!

 

[dixontj93060]

Very nice project.

 

[MarkH]

Wow. Nice Job.

By comparison, the commercial N record is about 44k ft.

 

[patelldp]

Seriously, the novelty of burning your fins off is very short lived. I have almost finished ripping off all the carbon to re-bag it. Not easy, sucks.

Wow, that does sound like a pain in the ass, considering when you are building it you intend for the CF to stay there forever.

Some sort of ablative material may be required for your types of speed. A phenolic insert between two pieces of G10 on your leading edge may be the ticket. Of course, you would have to route each piece to half thickness along the leading edge to allow for the insert which could be a pain. Additionally, you may still have the same aero-heating issue at the interface between the phenolic and the G10...

I'll keep thinking.

 

[JimJarvis50]

Great flight! Just curious, what did you do, if anything, to the leading edges and what kind of epoxy?

Nice field too! I wasn't aware of that location.

Jim

 

[Burner]

Great flight! Just curious, what did you do, if anything, to the leading edges and what kind of epoxy?

Nice field too! I wasn't aware of that location.

Jim

Thanks Jim. I used US Composites epoxy as I have a bunch of it and wanted to use it up. I did not do anything special to the leading edges.

I'm still trying to decide how the next iteration will pan out. I'll probably do what I didn't want to do and build a curing oven for a high temperature epoxy system.

 

[rfjustin]

Yesterday at the Friends of Amateur Rocketry site I reached a personal altitude record with my 98mm minimum diameter rocket on a research N2600 (~16,200N-s) to 42,305'.

NICE flight!



Justin

 

[patelldp]

Any aero heating evident on the nose?

 

[ClayD]

VERY AWESOME!

I saw this build on your site a few weeks ago, Glad to see you got it in some blue sky!...

 

[New Ocean]

42,000 feet! Very inspirational for those of us who mostly just dream about that kind of altitude.

 

[Obelisk]

Nice flight and great looking rocket!

Don't worry about the delam, DARPA has the same issue
https://www.foxnews.com/scitech/2012/04/23/pentagon-explains-why-hypersonic-mach-20-drone-failed/

 

[Burner]

Any aero heating evident on the nose?

Yep. Most of the paint is gone and some of it melted down the side of the airframe.

NICE flight!

Justin

VERY AWESOME!

I saw this build on your site a few weeks ago, Glad to see you got it in some blue sky!...

42,000 feet! Very inspirational for those of us who mostly just dream about that kind of altitude.

Nice flight and great looking rocket!

Don't worry about the delam, DARPA has the same issue
https://www.foxnews.com/scitech/2012/04/23/pentagon-explains-why-hypersonic-mach-20-drone-failed/

Thanks guys, it was exciting although I definitely had some luck on my side.

 

[rfjustin]

-6:1 Fiberglass von Kármán cone

Shockwave nose cone? If so, did you reinforce it at all?



Justin

 

[Burner]

Shockwave nose cone? If so, did you reinforce it at all?



Justin

Yes shockwave cone, but not a stock one. I had Jeff beef it up a bit for me with some additional layers of glass.

 

[bobkrech]

Thanks Jim. I used US Composites epoxy as I have a bunch of it and wanted to use it up. I did not do anything special to the leading edges.

I'm still trying to decide how the next iteration will pan out. I'll probably do what I didn't want to do and build a curing oven for a high temperature epoxy system.

A magnificant flight, but I have a few observations and comments on your fin damage.

Observations:

1. Carbon cloth will not melt. Hobby epoxy does.
2. If you layup the carbon cloth on one side of the fins and then the other, the epoxy will melt and the airflow will strip off the carbon cloth whcih is what appears to have happened.
3. Note the underlaying G10 is not damaged.

Comments:

1. Most commercial G10 panels use a bisphenol type resin that is cured at high temperature.
2. The stagnation temperature at Mach 2.3 @ 8 kft is only 290 C.
3. Heat transfer, not temperature, determines thermal damage.
4. Standard G10/F4 will easily survive short excursions to this Mach number without damage.
5. The stagnation pressure on the leading edge is 136 psi. This is more than enough pressure to peel back CF cloth if the epoxy melts if the cloth is not draped over the leading edge.
6. If you want to eliminate leadind edge damage and CF cloth layer peel-off, you need to drape the CF cloth over the leadind edge so that the high pressure airflow can not get under the CF cloth. Even if the epoxy melts and flows, the cloth will not be lifted.

https://www.aerospaceweb.org/design/scripts/atmosphere/ is a great atmospheric calculator that can calculate all the atmospheric parameters for any flight.

Bob

 

[SRP Crew]

Hi Burner,

Again, Congratulations on a +40k launch.
You've firmly secured the N2600 EXP record spot on the List. You're also 17th highest overall. Kudos on that alone.

This has been a good thread for showing the facts and results.
The rocket community can now push higher thanks to your rocket story.

Thanks!
SRP Crew

 

[Tominator 2]

A magnificant flight, but I have a few observations and comments on your fin damage.

Observations:

1. Carbon cloth will not melt. Hobby epoxy does.
2. If you layup the carbon cloth on one side of the fins and then the other, the epoxy will melt and the airflow will strip off the carbon cloth whcih is what appears to have happened.
3. Note the underlaying G10 is not damaged.

Comments:

1. Most commercial G10 panels use a bisphenol type resin that is cured at high temperature.
2. The stagnation temperature at Mach 2.3 @ 8 kft is only 290 C.
3. Heat transfer, not temperature, determines thermal damage.
4. Standard G10/F4 will easily survive short excursions to this Mach number without damage.
5. The stagnation pressure on the leading edge is 136 psi. This is more than enough pressure to peel back CF cloth if the epoxy melts if the cloth is not draped over the leading edge.
6. If you want to eliminate leadind edge damage and CF cloth layer peel-off, you need to drape the CF cloth over the leadind edge so that the high pressure airflow can not get under the CF cloth. Even if the epoxy melts and flows, the cloth will not be lifted.

https://www.aerospaceweb.org/design/scripts/atmosphere/ is a great atmospheric calculator that can calculate all the atmospheric parameters for any flight.

Bob

Bob,

What about something like using a higher temperature carbon plate or phenolic on the leading edges of the fins? Sort of like what the USC team did on the Silver Spur project.

I would think it would be hard to attach them. And you would need to have the tip to tip not cover the leading edges. Right?

-Tom

 

[bobkrech]

Bob,

What about something like using a higher temperature carbon plate or phenolic on the leading edges of the fins? Sort of like what the USC team did on the Silver Spur project.

I would think it would be hard to attach them. And you would need to have the tip to tip not cover the leading edges. Right?

-Tom

G10/FR4 plates are probably good to Mach 3 on hobby rocket flights.

Hobby rocket flight over Mach 3 probably should be made with carbon fiber cloth plate composites using Epon 862 (Bisphenol-F) or similar resin and Epicure Curing Agent W or similar linker processed at 175 C or higher. This material survives for minutes to hours at 300 C and will char and pyrolize under high heat load but will not soften.

Tip to tip layers is not relevant for stiff fins. Stiff CF composite plate fins should be attacjhed to the airframe with CF loaded epoxy with several layers of CF cloth formed like an L-bracket under a fillet of CF loaded epoxy. A single layer of CF cloth can be placed over the leading edge to prevent airflow on the plate edge after the L-bracket layers but before the fillet.

Bob

 

[New Ocean]

What about metal strips or high-temp epoxy by cotronics on the leading edge of fin?

 

[tfish]

I've used 'aluminum tape' on the leading edges of a couple of projects..unfortunately those projects got misplaced..and I'm not sure if the idea worked or not.

Tony