Level 1 Certification Success!

[downhill_D]

Aaaaaaand THAT is why I ask my questions HERE! Thank you! It is all coming together now for me. So the rounded edges are leaving a place for the molecules to pack up? and a tapered edge allows them to deflect at one nice angle. That is super cool and makes a lot of sense. This rockets leading edges are rounded and will be adjusted, for science data of course. I don't know why I rounded them, probably just easier. I guess this is why we have real rocket scientists handling to really important stuff.

Congrats. Welcome to HPR. Sounds like you have a great attitude to learning .

That is a great launch shot!

I would suggest you set the main to come out higher up next time, but I think you have already figured that out. Learn to design for sub-optimal conditions, particularly in recovery, and your rockets will thank you. It makes for safer flying too. Up is easy, down is hard.

FWIW I usually suggest that anyone certifying gives their camera to someone else to get pics of the event. Takes the stress off the flyer with everything else that is going on. YMMV.

Turns out I need to contact JL about the JLCR to see if the unit is defective or needs update?, I set it to 700 ft last weekend and it still waited till about 254 ft

 

[Nytrunner]

How fast is your rocket going?

For subsonic (incompressible flow), the rounded edges are great, they divert the flow optimally.

For super/transonic where the air compresses and the pressure and temperature goes wacky, the tapered edges divert the resulting shocks at a clean angle, whereas round leading edges would create multiple flow reflection disturbances. Look up Bow shock or Oblue shock

 

[downhill_D]

How fast is your rocket going?

For subsonic (incompressible flow), the rounded edges are great, they divert the flow optimally.

For super/transonic where the air compresses and the pressure and temperature goes wacky, the tapered edges divert the resulting shocks at a clean angle, whereas round leading edges would create multiple flow reflection disturbances. Look up Bow shock or Oblue shock

well it did 514 mph with an H180 but I want to run an H220 in it now. Thanks!

 

[Andrew_ASC]

Welcome to high power rocketry!

 

[downhill_D]

After zippering this poor rocket at Januarys launch on a windy day with too low an impulse for the wind...I ordered a new coupler and body tube and repaired this rocket for about $20 and a 1/4 shorter accidentily. No matter, weight and simulations still worked great. This last weekend I warmed it up with a G77-7 redline (Fantastic flight!) and followed shortly after with a G78-7 mojave (wow!!) an even more stellar flight! Next time I’ll send her up on one of my H220’s...after I have a tracker, the launch site is in a warm full growth spurt now which means thicker brush and rattlesnakes are out.

FYI: aerotech LMS motors are super easy to build on site and actually less complicated/faster than building a reload. I simply brought 5 minute epoxy to the site and waited about 20-30minutes to be extra sure it was cured before heating up in flight. These are awesome and I do prefer reloads but g sized redlines and mojaves are awesome! Here is the Mojave motor-courtesy of my friend Luke for the great photography-I believe this was his first time grabbing rocket photos off launch pads-possibly.

 

[blackjack2564]

Please be aware that although 5 minute epoxy "sets" up in 5 minutes, it does not reach full strength for 24 hrs.
Best to build LMS day before.
I have seen a few fail miserably when built and launched too soon.

 

[downhill_D]

Good to know!

 

[downhill_D]

This rocket went off like a bullet on an H220-10 last weekend-awesome flight! I need to fly it on an H220 again however because my ALT2 recorded good data except for the 5 digit top speed and 4 digit Top G's. I am going to mount it to the airframe inside and see if the results are more realistic. I would love to think I just brake a world record and made a LOC Graduator go 42000 mph and approximately 2400 G's but I am sure that did not happen or I have a time machine or a prize to collect. I'll post the data photo of the speed and acceleration. it's amusing. FYI I id mention this to Jolly Logic and he wasn't sure how it happened but to let him know if it does again. I have one more H220

 

[Nytrunner]

Woohoo! I've had the crazy numbers before also. How well was your Bay ventilated?

 

[downhill_D]

Woohoo! I've had the crazy numbers before also. How well was your Bay ventilated?

ventilated according to the altimeter port chart for 3 holes. What motor did you use? a fast impulse? My alt2 just hangs on kevlar cord at the nose cone so I am kinda surprised this hasn't happened before. I will be attaching it to the airframe for the next H220.

 

[downhill_D]

Yeah...world record there! This is MPH you can barely make the “m” out!

 

[downhill_D]

This graduator has officially retired ...I was expecting the usual 3220 ft altitude on an H-180 and after popping the nozzle out of the casing (o-rings got switched?) in the beginning of the flight it took a nasty swirl up for a moment and then it lawn darted. Once the fire was out the jolly logic chute release still worked but everything was destroyed, parachutes melted etc. The motor casing was still in the rocket upon recovery.

Irony of the day: I had just certified someone Level 1 before my own flight. I could only tell him "Don't do that." after my failed flight.

The H-180 white lightning RMS was the 29/240 casings 8th flight. I filed the MESS report and checked in with aerotech who graciously is sending me a used 240 casing and a new nozzle for free. Thank you very much to the warranty department at Aerotech! User feedback: perhaps color coded o-rings could be feasible for RMS motors in the future? Aerotech informed me I probably switched the fore and aft o-rings, a very common mistake on the H180, even among seasoned users. The casing and rocket will be in photos below as well as the list of motors the graduator flew on. I built this one strong but fire will always win. I will definitely make another graduator.

 

[downhill_D]

The rocket and casing

 

[Tobor]

Ouch....

 

[downhill_D]

Aerotech has already (in under a week) sent me a used 29/240 monster motor casing (serial #28), fore and aft closures. It is actually quite new looking inside and out! Thanks Aerotech! This is really nice!

 

[Scott Hala]

Congratulations!