David - 3" Flying Case to 60,000 ft

[diyaerospace]

Launch

I showed up to FAR on Friday night, April 5th. Thanks @vulpesjr and @tsbooska for helping me prep, you guys made integration go a lot smoother.

The vehicle was fully stacked around 2 am on the morning of the 6th.


After we woke up we got the rocket on the pad, armed electronics, and connected the ignitor.


Thanks @Neutronium95 for letting me borrow your tower and featherweight groundstation.

First launch attempt around 10am was scrubbed to a intermittent GPS connection, we got the issues fixed and launched around noon.

The EX motor worked great and had a beautiful plume. The rocket achieved a altitude of 41,800 feet and a max speed of around mach 3.
The drogue chute deployed and had a spicy descent rate(200fps ground hit).

We had good tracking down to 3,000 feet. Unfortunately, the rocket landed 5 miles away in the mountains around FAR. We went searching around the last transmitted coordinates but were unable to find anything.

We'll make another attempt at recovery next weekend.

 

[diyaerospace]

Photos from Julian Rice.

 

[diyaerospace]

 

[wclaybaugh2]

Launch

I showed up to FAR on Friday night, April 5th. Thanks @vulpesjr and @tsbooska for helping me prep, you guys made integration go a lot smoother.

The vehicle was fully stacked around 2 am on the morning of the 6th.
View attachment 639400

After we woke up we got the rocket on the pad, armed electronics, and connected the ignitor.
View attachment 639401
View attachment 639402
Thanks @Neutronium95 for letting me borrow your tower and featherweight groundstation.

First launch attempt around 10am was scrubbed to a intermittent GPS connection, we got the issues fixed and launched around noon.

The EX motor worked great and had a beautiful plume. The rocket achieved a altitude of 41,800 feet and a max speed of around mach 3.
The drogue chute deployed and had a spicy descent rate(200fps ground hit).

We had good tracking down to 3,000 feet. Unfortunately, the rocket landed 5 miles away in the mountains around FAR. We went searching around the last transmitted coordinates but were unable to find anything.

We'll make another attempt at recovery next weekend.

View attachment 639403

Were there winds at launch? The launch direction appears to be up range and to the south…not the usual westward track.

I also seems—to me—like a lot of drift on a reefed 18” ‘chute. Any reason to suspect the chute opened?

Bill

 

[diyaerospace]

Were there winds at launch? The launch direction appears to be up range and to the south…not the usual eastward track.

I also seems—to me—like a lot of drift on a reefed 18” ‘chute. Any reason to suspect the chute opened?

Bill

The launch direction and drift are both due to the fact that high level winds were brutal on the 6th. The chute likely did not open.

 

[Burner]

Awesome project, great job. I’ve misplaced a rocket in the same hills years ago, came back the following weekend and found it.

Out of curiosity, which epoxy did you use for the fin stock layup and what is the Tg?

 

[wclaybaugh2]

The launch direction and drift are both due to the fact that high level winds were brutal on the 6th. The chute likely did not open.

Looking at the trajectory cartoon, it appears that the ascent was near ballistic until about the last 10k feet or so; but the descent profile suggests a lot of wind until near the end, when the image appear to show a near vertical fall for the last few thousand feet.

Is this impression an artifact of the graphic or did the vehicle see less wind effect on the way up compared to coming down? If wind was a bigger issue coming down, do you have any thoughts on why that would be the case and—if the graphic correctly shows a neatly straight down trajectory at the end of descent—why did that occur?

Bill

 

[James Keller]

Looking at the trajectory cartoon, it appears that the ascent was near ballistic until about the last 10k feet or so; but the descent profile suggests a lot of wind until near the end, when the image appear to show a near vertical fall for the last few thousand feet.

Is this impression an artifact of the graphic or did the vehicle see less wind effect on the way up compared to coming down? If wind was a bigger issue coming down, do you have any thoughts on why that would be the case and—if the graphic correctly shows a neatly straight down trajectory at the end of descent—why did that occur?

Bill

It would appear and I may be totally wrong. But the first data point(maybe given by there vertical line) is very near apogee. Therefore it appears more ballistic then it actually is.

 

[ljwilley]

WOW that is a beautiful flame!

 

[wclaybaugh2]

It would appear and I may be totally wrong. But the first data point(maybe given by there vertical line) is very near apogee. Therefore it appears more ballistic then it actually is.

James:

Thanks, I had not tumbled that the vertical lines represented data points…dumb question, I guess.

Bill

 

[tsbooska]

Awesome project, great job. I’ve misplaced a rocket in the same hills years ago, came back the following weekend and found it.

Out of curiosity, which epoxy did you use for the fin stock layup and what is the Tg?

I used US Composites, which I believe has a heat distortion temp somewhere around 140 F. The LEs were coated in EP420NS, the same as the filleting epoxy, which is good up to about 300F if my memory is right, and that's taking a good chunk of the thermal loads. We'll see how it held up when it's found.

 

[diyaerospace]

It would appear and I may be totally wrong. But the first data point(maybe given by there vertical line) is very near apogee. Therefore it appears more ballistic then it actually is.

The vertical line is interpolation. The GPS locks out during most of the boost due to cocom limits. The first "actual" data point is near apogee.

 

[diyaerospace]

I've been considering that perhaps the nosecone and electronics separated from the rest of the rocket at apogee and fell separately. This would explain why I wasn't able to see anything while searching near the coordinates, as I expected to be looking for a big shiny motor casing.
It would also explain the lack of RDF pings from the tracker that was taped to the shockcord.

Oh well, we'll find out soon.

 

[diyaerospace]

I'd also like to credit @DabCat for casting propellant for the motor(Reliant Robin).

 

[Burner]

I used US Composites, which I believe has a heat distortion temp somewhere around 140 F. The LEs were coated in EP420NS, the same as the filleting epoxy, which is good up to about 300F if my memory is right, and that's taking a good chunk of the thermal loads. We'll see how it held up when it's found.

I’d be curious to see how it held up as well, even with the higher tg leading edge coating, there was likely enough heat transfer to begin delaminating the substrate. That may also explain the lower than predicted altitude. Did a similar project with US Composites a while back, results below.

Even so, awesome flight guys.

 

[diyaerospace]

Recovered!

We went out again on Saturday April 20th to try and find this thing, we were successful!




For the 280 fps ground hit velocity, it fared pretty well. Only damage was the fincan LE, chipped fins, and a damaged GPS tracker.



The fincan got smashed against the forward radial bolt ring on impact and crunched. Either way, i'm pretty happy with this result.





Here it is on the FAR altitude records! (Walter)



This was a world record for the highest flight by a independent high school group and highest recovered flight by a high school group.

Hopefully this build thread stands as a resource for any folks looking to tackle similar projects. I'm happy to answer any questions about the build that y'all may have.

Thanks,
Walter

 

[3stoogesrocketry]

Recovered!

...........

For the 280 fps ground hit velocity, it fared pretty well.

So this was a ballistic entry draging the cone.

 

[diyaerospace]

So this was a ballistic entry draging the cone.

Yep, defiantly didn't intend for it to descend like that. I'll be using bigger chutes in the future lol

 

[diyaerospace]

Threw together a video on this project for fun.