Reaper Level 3 Cert Build

[H. Craig Miller]

The purpose of this thread is to present and document my Level 3 Certification build, which I call Reaper.

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Although this thread will primarily be through photos, I will update the thread and answer questions as I can.

 

[H. Craig Miller]

The Reaper build is divided into 3 main sections (Booster, AV Bay, and Nosecone), with the Booster being subdivided into 5 subsections, the Tail Cone, Booster (with fore and aft extensions), and Drogue Payload Bay.

BOOSTER SECTION

Tail Cone:

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The motor retainer is a 75mm Giant Leap Slimline Retainer.

 

[H. Craig Miller]

Motor Tube:

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Installing the shock cords is a two-step process.

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[H. Craig Miller]

Fins (Forward):

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Splitting the forward fin was necessary to facilitate beveling of the edges. The second picture shows the wedge that was epoxied into the joined edge for strength.

 

[H. Craig Miller]

Drogue Parachute Payload Bay:

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The foregoing is the construction of the coupler that connects the drogue parachute Payload bay to the Booster Section. The bay itself is a 12" airframe extension.

 

[H. Craig Miller]

Booster Subassembly:

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[H. Craig Miller]

Drogue Parachute Payload Bay:

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[H. Craig Miller]

AV BAY SECTION

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The upper lid is 4 layers of 1.5mm black G10 on the top and 1 layer of 1.5mm black G10 on the bottom.

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Primary Altimeter

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Shock Cords

Because the weight of the rocket is only about 15 lbs., 1/4" Kevlar shock cord material is adequate.

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[H. Craig Miller]

NOSECONE SECTION

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Head-end recovery, with an adjustable weight bay.

 

[H. Craig Miller]

Build complete, except for the avionics...

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Anticipated flight characteristics...

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On to ejection charge testing... first two videos are with empty bays... the second two videos are with parachutes loaded.

 

[tim cubbedge]

Nice! When you going to launch it? Good luck!

 

[teepot]

Very nice

 

[H. Craig Miller]

LDRS, hopefully.

 

[H. Craig Miller]

Could not ask for a straighter flight...

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[GrouchoDuke]

...aaaaand, did you win!?

 

[H. Craig Miller]

Regrettably, though the flight was perfectly straight without any deflection, and the drogue deployed perfectly, the HED main refused to come out of the nosecone. A few lessons learned. Re-Reaper will NOT have head-end deployment.

I did learn a few things about temperature, fiberglass tubing, and ejection charges. When the rocket was put on the pad, its internal temperature was 102 degrees, at launch it was 113 degrees, and at apogee it was less than 85 degrees. Those temperature swings can have a significant effects on the separation at ejection, as well as the amount of the ejection charge needed.

I learned something else useful too. Powdered graphite lubricant is not just for pinewood derby wheels, it works to lubricate fiberglass couplers (and other mating surfaces) too. Just wished I had known that before my flight as well.

 

[GrouchoDuke]

Oh, man. Sorry to hear that. Lessons learned are great, but that still hurts. Looking forward to Re-Reaper!

 

[Jmhepworth]

I learn more from my mistakes than from my successes. Good luck in the next try.

 

[crossfire]

Regrettably, though the flight was perfectly straight without any deflection, and the drogue deployed perfectly, the HED main refused to come out of the nosecone. A few lessons learned. Re-Reaper will NOT have head-end deployment.

I did learn a few things about temperature, fiberglass tubing, and ejection charges. When the rocket was put on the pad, its internal temperature was 102 degrees, at launch it was 113 degrees, and at apogee it was less than 85 degrees. Those temperature swings can have a significant effects on the separation at ejection, as well as the amount of the ejection charge needed.

I learned something else useful too. Powdered graphite lubricant is not just for pinewood derby wheels, it works to lubricate fiberglass couplers (and other mating surfaces) too. Just wished I had known that before my flight as well.

How did you pack the main chute area? Plus where was main chute attached?

 

[Donnager]

Regrettably, though the flight was perfectly straight without any deflection, and the drogue deployed perfectly, the HED main refused to come out of the nosecone. A few lessons learned. Re-Reaper will NOT have head-end deployment.

I did learn a few things about temperature, fiberglass tubing, and ejection charges. When the rocket was put on the pad, its internal temperature was 102 degrees, at launch it was 113 degrees, and at apogee it was less than 85 degrees. Those temperature swings can have a significant effects on the separation at ejection, as well as the amount of the ejection charge needed.

I learned something else useful too. Powdered graphite lubricant is not just for pinewood derby wheels, it works to lubricate fiberglass couplers (and other mating surfaces) too. Just wished I had known that before my flight as well.

Graphite is great, if not messy.

Ground molybdenum disulfide works pretty well to dry lubricate cardboard, also. I still have a couple vials of this "mess in a bottle" obtained for Pinewood derbies that I use sparingly.

 

[H. Craig Miller]

Here is the post-crash restoration... damage and repair...

Damage to one fin:

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Rail guide repair [cosmetic]:

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Significant airframe damage:

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Nose cone [complete replacement]:

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Ready to fly... again.

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Now, off to Oktoberfest with Tripoli Las Vegas... hoping anyway.

 

[teepot]

Another great looking rocket I get to see. I sure hope the weather cooperates.

 

[H. Craig Miller]

This time, I want to see what the flight looks like... up close and personal.

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[Bat-mite]

Looks great. Best wishes for take two!