Gt-R - A 29mm MD Rocket - Build Thread - MIA

Today I was able to get the red paint sprayed. I was hoping to get the black on as well but the paint was still too wet to do anything else with it today.

I just tried to upload the photos to this post but the forum REALLY doesn't want me to... I'll try to get them posted somehow. I'll try my phone and if that doesn't work I guess I'll just have to describe the paint job to ya'll in detail.

Let's hope this works.

RAHagen said:

Let's hope this works.

Click to expand...

Looking good man, that is a lovely rocket.

Black is on the rocket! Now all I have to do now is print out the decal and clear coat. Yesterday I ordered the motors for it and will be launching it on the 11th!

SinfulDarkLord said:

Looking good man, that is a lovely rocket.

Click to expand...

Thanks! It definitely couldn't have gotten to where it was without the help of you guys on the forum.

Here is the rocket all put together. I got the decal printed. Hopefully I'll get it on tomorrow along with a clear coat.

I decided to simplify the the paint job to cut down on the amount of decals on the rocket. It still looks good though.

Okay I'm getting ready to apply the decal to the rocket but before I do I'm going to drill the pressure release holes. I already drilled the static holes for the altimeter and for the upper airframe, but I'm not quite sure how large to drill the hole for the lower airframe. I'd be afraid of drilling it too large but I DEFINITELY don't want to drill it too small.

Do you guys have any hole size suggestions for the lower airframe? I used a table I found online for the av-bay but I'm not sure about the airframe. It suggests the same amount of holes and the same size but they seem small..

Okay well I decided to just pick a hole size and go with it. I'll bring my drill along with me to launch just in case someone says I should drill it larger.

After the hole was drilled I applied the decal and just this morning I clear coated it making GtR officially completed!

I'll post pictures after the clear dries.

I want pics NOW...

codysmith said:

I want pics NOW...

Click to expand...

Haha well it just so happens that I now have them.

Sadly the decal had a few bubbles that fogged up a bit when the clear went on, but the same thing happened on my cert rocket and those slowly faded away. Fingers crossed!

Over all I'm very happy with how the rocket has turned out and I am really looking forward to seeing it launch on the 11th!

I'd like to say thanks to all the people on here who helped me with this rocket and pointed in the right direction. Without the people on this forum this rocket would have been radically different.

Well GtR did not fly last Saturday. I got all the way down to the launch site and noticed that I had forgot to bring one of the most important parts of the rocket: the electronics mount! Without that to mount a tracker, I couldn't bring myself to launch it. Next launch date with my club is in late August so I will try again then.

A quick update. GtR has still not flown. Problem with Texas is that burn bans are all too common and fire marshals don't very much like the idea of rockets during a ban. So at the moment launch date is unknown. Hopefully soon but burn bans can continue even after rain. For once rain will actually help my rocketry hobby.

Total bummer man, I know. Stick with it and hopefully we'll see it fly soon!

I just read through this thread. Very educational. I hope you get to launch it soon.

Bat-mite said:

I just read through this thread. Very educational. I hope you get to launch it soon.

Click to expand...

Thanks Bat-mite! I'm learning a lot as I go as well. I'll keep this thread updated on the progress of launch sites.

Well then I thought I'd resurrect this thread to say that as long as the Texas weather cooperates Gt-R will be flying at the end of the month! Did a charge test yesterday and despite the fact it was tremendously over powered (singed the parachute pretty bad) the rocket is ready to finally make its debut! Let's just hope the stars align and the weather will cooperate.

Cool, good luck!

Dont forget to take a video, good luck on the flight.

pyrobob said:

Cool, good luck!

Click to expand...

SinfulDarkLord said:

Dont forget to take a video, good luck on the flight.

Click to expand...

Thanks guys! Still holding out for the weather but I'm hoping for the best!

Gt-R's launch date has been move up! Gt-R will fly today! We're driving to the site now. Plan is to do a shakedown flight on an AT G80 and then push it up to the I205! The pre-launch jitters have started and I'm getting a bit anxious. I'll post a launch report as soon as I get home!

RAHagen said:

Gt-R's launch date has been move up! Gt-R will fly today! We're driving to the site now. Plan is to do a shakedown flight on an AT G80 and then push it up to the I205! The pre-launch jitters have started and I'm getting a bit anxious. I'll post a launch report as soon as I get home!

Click to expand...

Good luck

Success! Gt-R was my first flight of the day. I flew it first on an AT G80T and it went to 5000 feet and reached mach .8. The rocket under preformed in comparison to the sim - 1000 feet lower and 100 mph slower- but I'm still VERY happy with the flight. After that I planned on jumping to the I205 however I decided to fly it on a cti G106 skid that grouch gave to me. Thanks grouch! On that flight it flew to nearly exactly the same height and altitude (the flights were within a hundred feet of each other). The fly-away rail guides worked flawlessly! Love these things, and plan to buy a pair for my soon to be built 38mm MD.

There is a downside - the streamer was not large enough to slow the rocket. On both flights the rocket hit the ground at 50 MPH. Due to that, on the second flight, the rocket hit the ground wrong and it cracked one of the fillets. By the time I had fixed it, it was too late to launch it on the I205.

Oh well, something to look forward to.

Congrats man! Pretty sure I got one if not all on video. Will post as soon as i work it out....

Congrats. It's been a long wait to get that one in the air! Very nice indeed!

Congrats man, glas to hear all went well.

Thanks Guys, well now that I'm home and had a while to look at the data I can give you guys a bit more of a complete flight report.

Flight #1 - AT G80T-14

[video]https://youtu.be/BOb_T1oLpeU[/video]



Thanks to my awesome Telemetrum I got some pretty nice 3d flight profiles and flight data. According to the electronics, the rocket flew to a max altitude of 5012', reached a max speed of 548 Mph or Mach .7, and achieved a maximum acceleration of 24G's. The rocket veered slightly after leaving the pad, but I believe I can attribute that to the fly-away rail guides not fitting perfectly on the rail.

Flight #2 - CTI G106 SK-14

[video]https://youtu.be/uPw_QSMLE2c [/video]



The rocket's second flight was nearly identical to the first performance wise. The rocket flew to a max altitude of 5059', reached a top speed of 526 Mph, and had a max acceleration of 25G's. This flight was nearly perfect in many ways. The rocket came straight off the pad and landed only a couple hundred feet away The only downside to the flight was that the streamer was not enough to slow the rocket down, and one of the fillets cracked on landing.

So with this information, it's clear that although the rocket flew wonderfully, it did under perform to an extent. In both flights the rocket's altitude was around 1000' lower than in the simulation, and the rocket's speed was around 100 mph slower. It also didn't break Mach 1 as I had originally intended this rocket to do. Although that's a bit sad I was extremely happy with it's performance, especially with how well the airframe held up. I'm looking forward to sticking the I205 in it next month. Plus I've still got one more trick up my sleeve for breaking mach on a G motor: the G138T. The sim file says it should reach Mach 1.15 so I'm hoping that with the kick of a HP G like that I can get this rocket to go supersonic.

Yes, be happy with two successful flights!

Was a pleasure to meet you in person and really enjoyed seeing the second flight of the rocket on the skid. Great!

Yea, that little thing flew very well. Gongrats on a successful shake down.

Very cool man.

Well I thought I'd update this thread to inform y'all of the sad occurrence that happened a couple weekends ago. After repairing the cracked fin, I flew Gt-R on an Ellis mountain H50. I had telemetry all the way up and down. The problem was that it came down too fast... Parachute did not deploy and as far as I am aware it hit the ground near 250 mph. After following the last transmitted GPS signal we found no trace of GtR. My only guess is that there is a 29mm hole somewhere in the area of plowed field we were at.

The rocket did reach 9500 ft which is a new record for me! But I never found it and my last hope is to go down there with a metal detector before the owner disks the field.