A Level 2 Story

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LaneKG

Well-Known Member
Joined
Apr 29, 2003
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TRF,

My Level 2 project was a BSD Thor. 4 in diameter, 85 inch tall rocket, with 54mm motor tube. I decided to embellish basics for this level 2 project, so I went for a Slimline 54 mm retainer and a 38 mm Slimline Motor Adapter from Giant Leap. For recovery, I upgraded to the Rocketman R7 Chute with deployment bag and a 24 in Rocketman drouge. ( I actually got to chat with Ky the Rocketman.)

Having chose to go dual deploy, I decided to use dual altimeters a RRC2 and a MAWD. (Failure was not an option) I chose the MAWD instead of a second RRC2 for its logging capability. The Thor couplers were six inches (too short for the RRC2) instead of the usual 7 in, so I used the whole 10 in payload section plus 1/2 coupler on each end as an electonics bay. In the electonics bay, I decided to use the Missle Works 110/220 switches. Against the usual advice about switches, I went with a power switch and a shunting switch on each charge. So that is three switches for each altimeter and six switches total.

I used the RGM altimeter hardware that has a 1/4 inch all-thread through the bay and loop hardware at each end. He also had mounting plates for the altimeters that would slide onto the all-thread. Each altimeter was setup to fire a apogee charge and a main charge. That is four charges total. On the main side I used used empty D motor cases for charge holders. I bought some premade canisters with ematches from Quickburst. They were loaded with 50 grains of BP.

The motor for this level 2 launch was the Aerotech J350. All this gear made for a heavy Thor about 8.3 lbs without the reload. (Perhaps it was the miles of wire you need for six switches.) The CG was at 50 in and the CP at 70 in. The RockSim gave me apogee at 2700 feet. I fly with SEARS 572 and the appointed Cert attempt was at the Sept 11th Patriot's Day launch. That yielded the Red, White and Blue color scheme.

All of this was not designed up front. I made all these choices along the way. I thought up a many ways to do the altimeter bay and that part took the most of the time. Six switches yields a lot of wire runs. The paint scheme came down to the last days. It actually was 11PM the night before the launch that the altimeter settings were figured out and the harness was hooked up. One part that was not last minute was a BP test a few weeks prior with the help of John Hansel who did his level 2 with a 1/2 Scale Patriot on the same day.

For the launch day, we had low clouds and light rain at the Samson AL launch site, so it was challenging to get the reload built and keep it dry. In the PM the sun and blue skies came out. John Stein RSO'd the Thor and gave me some tweaks which included putting a small hole in the main payload section to reduce the vacuum pulling against the nosecone. This was my first dual deploy, now that can make you have a case of the nerves. Especially with two hundred dollars of electronics on the rocket. For that final touch of gold plating, I put on a Trans-Beep locator on this bird.

Yes and the long awaited countdown yielded a slow and low flight with some weathercocking into the wind. The drouge came out, then the main. This trajectory caused the Thor to float in front of the spectator area (almost a fly-by.) It turns out all four charges burned. The RRC2 readout was 2125 ft and the MAWD was 2030 ft.

Now I feel some great relief as I am sort of a worse case thinker. Well, in reality the best case happened, everything worked. I actually owe the success to Rev Keith who kept checking the status of the Thor each week. This kept me pushing to make it happen. Did I say I can procrastinate a bit? This was a December 2003 to September 2004 effort. Well I charge three months to BSD's delivery but it was well worth the wait.

Thanks,

Greg Lane
Panama City, FL
SEARS 572 President
www.sears572.com

Pics/Video at https://sears572.com/gallery/GregLaneLevel2Thor

Try the slideshow at
https://sears572.com/gallery/slideshow.php?set_albumName=GregLaneLevel2Thor
 
Wow.. Very cool..:) Nice rocket, great flight, and an awesome looking DD setup.. Apart from the convenience, DD is just plain cool...:D Kudus on the L2!
 


Well Done Mr. Lane...!!!

Glad you could get it done before the storms hit... I hope you and yours survived without any major problems...
Now you need to bring that masterpiece rocket up-state and show us city boys how it's done...!!!

 
First of all, congratulations on your cert.
That's a fine looking rocket.
What I am wondering about is your alt. bay.
I'm attempting my first dd.
I am modifying a P.M.L. Quantum Leap.
My alt. bay is somewhat similar to yours and
sort of heavy at 1lb.11ozs.
What I'm concerned about is the cp. cg measurement.
Now please keep in mind , I am fairly new to this as up till now I
have only flown stock rockets.
Anyway, everything I have read says the cp.-cg. should be 1-2 calibers of the
rocket.
I am over that and you are or were at 20'' or 5 calibers.
Is there something I'm overlooking.
I'm kind of panicky at this point as I have quite a bit of time and $$ sunk into this thing.
And untill I read your post I was thinking this rocket was headed to the Rocket Museum without ever being flown !
Thanks in advance for any help.

Greg
 
Greg,

The several calibers of distance between the CP and CG makes the rocket over stable. The impact is going to be that the rocket weathercocks. So if you are overstable I would stick to light winds at launch time. I think the margin on mine backed off a caliper when I loaded the J350. So you really need to account for the motor you are going to fly. If I moved into larger motors I would be OK because I would less overstable but not understable.

I am guilty of over building a bit. I built up a Estes V2 to the point it took a G64 to fly it. It made a nice rocket.

Steward and Justin,

Thanks for the compliments on the project. I'll have to fly it on a regular basis to get further return on my investment.

Thanks,

Greg
 
Level 2 certification qualifies you to purchase and use J, K, and L engines

Thanks,

Greg
 
Congratulations Greg.
Nice rocket and nice flight.
I was suppose to fly my L2 today but sadly work got in the way of that.
 
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