CJ's LDRS 35 Punisher Sport Drag Race 35.00 build.

[blackjack2564]

Finished the Punisher SS. and flew it last launch on a AT H-123. went 2462ft.

Used .75 g BP for apogee and .6 for main.

2-256 shearpins in nose cone & 1 vent hole [in cone above coupler/shoulder] 7/64th's to prevent Cone separation under thrust.

36in. Topflight chute & 15 ft of cord for main. 9 in. nomex chute protector. Chute rolled burrito style.

12in TF for drogue with 6in nomex protector. This is set up dual deploy. [obviously...LOL]

Rail buttons are just above rear of airframe & right at top of motor mount tube. Just drill 1/8in holes and self tap/screw the rail buttons in. They hold just fine like this, been doing it for years.[even on 4in rockets] See 3rd pic on right.

Here's some pics of finished rocket.



Edit:

I run the power wire for GPS out the same hole used for e-match.
At launch , I power up by twisting wire, taping to BP on bottom of NC.
I do this at my table/truck...stick on the NC, insert shear pins & ready to fly.
This also gives the GPS time to "lock" satellites, so I have a "hot" start at pad, rather than a cold, & waiting for lock.

 

[ksaves2]

Nice setup. My only comment would be to do an adequate range test out in the open if one were going to really punch it up with a more powerful motor like an I. The 250mW Xbee might be able to overcome the folded antenna but if going for maximum range I'd look at a different arrangement.
One alternative would be an aft facing SMA bulkhead mount something like this: https://www.ebay.com/itm/4-RP-SMA-F...607419?hash=item1a071ec7bb:g:bZ0AAOSwd0BV7CdD
Could perhaps solder an SMA or SMA-RP socket on the XBee and then run an interconnect to the aft bulkhead. That would get the antenna out in the free air after ejection. Yeah, might risk antenna damage but that's what the screw-in socket is for. Easy replaceability.:wink: Could use something like this: https://www.ebay.com/itm/Antenna-SM...726974?hash=item464e70d07e:g:1csAAOSw~oFXGQ6v
There's a variety of antennas one could try.

The longer that Punisher is out of sight at altitude, the better the data link one needs to keep tabs on where to look for the main when it
gets to the deployment altitude.

I have a Wildman Jr. that routinely does disappearing acts on J's even if it lands 1/2 to 3/4 of a mile away with a fully deployed main chute. Get past a mile and even with a nominal flight, it won't be seen. The Beeline GPS works every time in that situation. Kurt

 

[wyo17]

CJ,

Here is Sundays Drag race.

Tim was 1st off the rail.

 

[blackjack2564]

Nice setup. My only comment would be to do an adequate range test out in the open if one were going to really punch it up with a more powerful motor like an I. The 250mW Xbee might be able to overcome the folded antenna but if going for maximum range I'd look at a different arrangement.
Kurt

Well........Already done that at Airfest last year. Flew the Punisher 3in to 16,661 ft [3 miles up]with same set up [folded antenna] Boom'n signal...landed 2 miles distance. Walked right up to it.[after a short drive...LOL]

But your advice is sound. Every build may have slight inconsistencies & needs testing. In my case I had a RF [falcon Comm-Spec} on board as back up for that first high flight.

 

[ksaves2]

The 250mW transmitter is likely helping along with a good receiver design. Ah yes, very smart to have a backup in uncharted territory. Kurt