Nike Cajun 2 stage MPR

[Charles_McG]

Well, heres a update on flight #2, the velocity lock was engaged ( because I feel that there need to be altitude lockouts lower than 300' the alt check was disabled). Staging did occur but rocket was horizontal away from flightline when it occurred, even with the timer set to one second less than previous flight on the same booster motor ( an F24W). The Quantum also did not fire the deployment charge at apogee and booster came in ballistic, possibly rebuildable, but I probably wont. Aluminum sled angles and all threads bent, one terminal block, the beeper and one other part were shorn off the board ( verticle 3 pronged thing between main drogue terminals). I will be contacting Cerving, for parts to see if I can fix it to recover data from flight. The JLCR's op rod was also bent but after straightening it worked fine, but I do need to contact John Beans for a replacement.
Will post photo this evening when I get home.

Sad to hear.

Is the Quantum alive enough to get the data from? So you can see what -it- thought was going on?

 

[rharshberger]

Maybe, I haven't had time to mess with it since last afridays crash.

 

[BDB]

This is sad. Do you have an explaination for why the rocket turned horizontal during the first stage boost? And do you have any idea how lockouts could have been used to prevent booster ignition?

I’m asking because my last flight successfully ignited the sustainer too, but I used pretty “loose” lockout conditions.

 

[rharshberger]

I used very loose lockouts, no altitude and velocity check 100 fps, and I currently have no idea what went wrong ( the rocket wasnt truly horizontal, as the sustainer gained an additional 200'-ish of altitude acvording to the JL3 riding in the payload bay). I do need to compare data between the two Alts if the quantum will still work and data is recoverable. The impact broke the wire at the power terminal block and squished the lipo pretty badly ( thank goodness it did start burning).

 

[rharshberger]

Good news is that the Quantum once the bad components were removed from the board (one FET was sheared off and the terminal blocks wrecked, as well as the buzzer damaged) the unit powered up and communicated so I was able to get both the .csv file for the failed flight and do a memory dump for Cris.

 

[AlphaSigOU]

Wanna try an odd scale rocket? This is the Nike-Apache currently on display at the Roi-Namur air terminal at Kwajalein Atoll in the Marshall Islands. (Nike M5E1 booster without fin shroud and basic Apache upper stage.)

 

[blackjack2564]

It was an interesting project, too bad about it's demise, before you could really get the feel for it.
Ah but don't let that get ya down, try again.
I won't even mention the moola some of my.... ahem ...lost , destroyed etc. 2 -stagers cost.
But the joy of a successful flight, make all the bad stuff go away, cause you are doing something few attempt, & even fewer succeed .

Good luck on the next one!

 

[rharshberger]

It was an interesting project, too bad about it's demise, before you could really get the feel for it.
Ah but don't let that get ya down, try again.
I won't even mention the moola some of my.... ahem ...lost , destroyed etc. 2 -stagers cost.
But the joy of a successful flight, make all the bad stuff go away, cause you are doing something few attempt, & even fewer succeed .

Good luck on the next one!

I know CJ its been a long time since you posted to this thread, but tonight I was fiddling with the busted up parts to the booster (sustainer survived just fine), I only really need to rebuild the ISC (cardboard and paper with paper shroud), a new AvBay coupler, new Eggtimer Quantum (planning to buy three next Eggtimer sale), and a new section of aiframe. The fincan survived and I have enough space to put about 2" of coupler into the old fincan. This bird will fly again, maybe not till winter but it will fly again.

 

[BDB]

Ouch!!! This staging-stuff is really hard, as demonstrated recently by me, Charles and now your two flights. I wonder if it is even harder in the MPR range because we are so close to the safety lockouts. What do you think happened? (I’m guessing that a F50 in the booster might get it moving faster off the pad and that might solve some of the issues.)

 

[rharshberger]

After consulting with Cris we determined that it was indeed too close to the safety lockout for velocity. I used a 4 second from lanch delay for sustainer ignition and probaby dropped to below 100fps until acceleration after apogee pushed it back over 100 fps (apogee ejection charged failed to fire). Correct time should have about 2.3 seconds.Need to work the kinks out now, should be a reasonably quick fix but the Quantum is all dead.

 

[rharshberger]

Just got the parts yesterday to do the rebuild on this bird, and I will be ordering the Quantums this weekend.