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L1 Attempt - No Joy

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edwardw

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Yesterday I flew my creation - Unfinished Requiem for my L1 attempt at our three day Springfest launch.

No Joy.

Flew on a Pro 38 H153. I had dual deploy set up because of the wind - rockets were drifting 1-2-3+ miles A guy never found his 2 stage K rocket - live telemetry said 18k feet.

Rocket went up - at top the rocket split - drogue-less dual. Then at 500 feet nothing happened. Until it met the ground.

It hit the ground, cracked both body tubes. No cracked fins though - TTW works great. The electronics were okay - reported 2244 feet - and the rental 2 grain case were fine. It's okay - I'm going to rebuilt nearly the same rocket and fly in two more weeks at our May launch.

Post analysis says the main dual e-matches didn't fire - at all. I went back to the truck and hooked it up to the computer - left everything the same as I found it on the ground and hit the "Test Main" button. Both lit like the 4th of July. Bah.

On other notes - we had a great day though. I think there were 5 cert attempts - 2 L2 and 3 L1. Lots of fliers. We had 2 catos - on BP motor and one K motor that shot flames out both ends.

There was a group M3000 project - very cool. Only bad part was it tore the fins off at about 1000 feet - was still stable to keep climbing - then no electronics were working so it core sampled about 2000 feet from the tower. Sad time. Sure is cool to see that huge flame.

Well, I'll keep you updated in two weeks and I will have some build pics. Here is a picture of me with the rocket before the flight.

Edward
 

slim_t

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Sorry to hear it.
Better luck next time.

Tim
 

eugenefl

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Originally posted by Ryan S.
bummer

btw that feild is awesome
No joke. Nice field. Best of luck on the next attempt. You should do just fine.
 

edwardw

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Since you like that field I just HAVE to show it off with a few more pictures. We have square miles upon square miles of area to play in :)


Here is one with the gang coming back after the M3000 was prepped.
 

edwardw

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Here is one showing the line of cars and people we had. We even had quite a few that camped over night for the 3 day launch. :)
 

edwardw

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Here is one showing my rocket coming down with no chute... :( But I was 200 feet from pad :)
 

edwardw

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Our website is

www.ncrocketry.org

We fly from two sites - the ATLAS and the NORTH. The Atlas site is about 40 miles east of Fort Collins on CO Highway 14 and about 1/2 mile north of the highway. It is located by an old Atlas Missile complex that has been covered with dirt.

The North site (what is in the pictures) is about 35 miles north of Fort Collins and on Highway 85. It is 8 miles east of the highway. There is NOTHING around. Just cow pies and cacti. There are some really cool mesas just to the north of there. It is 16 miles south of Cheyenne, WY.

Both sites are on the Pawnee National Grasslands. Great fields and lots of room to recover - no worry about trees or keeping in the field. :) Just worrying if it drifts will you ever find it again.

Edward
 

g_boxwood

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Originally posted by edwardw
Post analysis says the main dual e-matches didn't fire - at all.
Sorry for the obvious question: how about the battery? Did you load test it prior to flight? If yes (and I'm sure you did), how many Amps? You said dual e-matches: did you have 2 altimeters? If yes, that for sure reduces the odds of battery failure.

I witnessed 2 flight profiles as yours: in one case (friend of mine L2 2nd attempt w/ LOC Magnum) the main charge didn't fire because of a poor battery (tested AFTER the flight); in the other case (L3 2nd attempt w/ a scratch behemoth on M2500T) the main didn't come out probably because of a coupler super-tight fit (during the previuos attempt both 'chutes deployed at apogee and the guy THIS time wanted to make sure that the main DIDN'T... not at all BTW).

One last thing: commonly it is said to discard batteries whose Amp reading is close to 2; better to be on the safe side and discard them if they don't provide around 4; the post-reading revealed around 3... A fresh (BUT LOAD TESTED) battery for every flight is well worth the investment... (it can be used in other application then).

Ciao,

Giacomo
 

edwardw

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They were brand new batteries. I was using low current e-matches for the Perfectflite MAWD. I ground tested the system 4 times to make sure. Even worked on a battery that only had 7.5 volts. Both batteries were fresh and had over 9 volts and could supply the amps needed. No reason why they didn't work. I had two 9 volt batteries in parallel just to make sure that I had the power. No reason the matches didn't fire - just didn't. And when I ground tested them after the flight - the only thing I did was take the wreckage - hook up to computer, acquire the altimeter and hit the Test Main button. Didn't disconnect the batteries at all. It happens. The altimeter works fine - I did some testing in my ad-hoc vacuum chamber here. Fires both channels every time. Next time It will work :)

Edward
 

g_boxwood

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I was supposing right about your pre-launch preparation then.

I'm sorry, that was real bad luck in the end. Which is part of the business BTW.

Sure it will be a success next time!!!

Ciao,

Giacomo
 

Johnnie

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Ouch, sorry to hear about the no joy...and yes, the field rocks!

Love the design of your L1 bird, when do we see detailed photos?
 

edwardw

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Johhnie,

I had my fiance's nice digital camera for the build - but always seemed to have epoxy covered latex gloves so I didn't get any pics. For my next one I will get nice pictures - my father now wants to build an L1 bird so I'm hoping to make a pictorial for him to kind of follow. But - here is the Rocksim file of the new rocket :)


Edward
 

scm86

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were the wires in good? Ive got a the same alt, i on occasion miss the tab that traps the wire, could be that you did the same, didja pull on the wires to make sure they were in tight?

on the Cert attempt, youve got a one up on other normal flyers, most people goin for certs havent flown an H yet ;-)

Scott McNeely
 

edwardw

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Yep - everything in okay - they fired fine on the ground with no modifications done to it. Just didn't fire. No explaination. Hey, if it were easy everyone would do it.

Edward
 

RocketboyG80

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One more question Ed, you say you have a MAWD, did it do the triple continuity beep when you armed it? The reason I'm asking is 'cause I flew my Legacy yesterday with the MAWD set for dual deployment. It did the triple beep but it never fired the drogue. Although it did deploy the main, but at high speed, which caused some damage from the Kevlar shockcord whipping back. Although it was a good flight up until ejection, or lack of it. It got 1,695 feet on a G64, kind of low but my dual deploy setup is a little heavy. It landed a good distance away in a swampy area but no damage besides the small zipper.
 

edwardw

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Had the triple beep - or as my Dad calls it - get outta there - she's gonna blow...as he runs away comically. The ejection charges each were Ohm-metered for matching. I'll rebuild...maybe even this time a relay control board AND the MAWD...something that will take the signals the MAWD gives to it and fires yet another redundancy channel in addition to firing off two e-matches. Hmmm... (evil grin)..I guess I'll see how well that would work. I see some SCR's in the future and another 9V battery. Sandman - you have any suggestions on hooking up an altimeter to a SCR - I know you work with them....

Edward
 

UhClem

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I am not sure why you used two parallel 9V batteries with your MAWD. This altimeter uses a large capacitor as the current source for firing the outputs and the current rating of the battery has no impact on how much current is available to the E-matches. A standdard 9V alkaline should run the altimeter all day.

Plus, the manual quite clearly claims that the MAWD can fire up to 10 paralleled E-matches.

If the MAWD did not use capacitive discharge, it might burn up its output FETs. Judging by the pictures of the altimeter, these are small surface mount dual FETs similar to the IRF7101. While these parts have reasonable current ratings, their power dissipation is very limited. This part will last less than a tenth of a second if it switches a 9V battery into a short.

Have you downloaded the data recorded by the MAWD? It might give you some clue as to what the problem is. Since you were able to command the altimeter to fire its outputs on the ground then one possible failure mode is that the altimeter never decided to fire them during flight.
 

scm86

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now theres an idea, what is your guy's altitude MSL? if you set it at 800 and your at 850, then your not gonna get a deploy unless it falls in a 50 foot hole...

Scott McNeely
 

firemanup

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Sorry to hear about the problems ed.....

keep at it..

My level one took three times.. delay blowby, followed by delay blowby, followed by switching to Pro 38.. and a good cert flight...

Good luck on the next one...
 

Rocketjunkie

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Originally posted by scm86
now theres an idea, what is your guy's altitude MSL? if you set it at 800 and your at 850, then your not gonna get a deploy unless it falls in a 50 foot hole...

Scott McNeely
The altitude is AGL. The altimeter reads the altitude while sitting on the pad waiting for liftoff and uses this value as zero.
 

scm86

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I stand corrected... o well, ya win some, ya lose some...

Scott McNeely
 

RocketboyG80

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Today I ran a test of the still loaded ejection canister. Unlike before the flight, it now has no continuity, therefore I assume the filament actually did burn. All I can figure is that the little filament just wasn't hot enough to ignite the BP charge. Although, I've used those Pratt ejection cans before, and they usually go off instantaneously. All I can the think of is that maybe the BP somehow got some moisture in it, although that doesn't explain why the main charge did work and this one didn't. I keep a small portion of BP in my range box in a film container and that is what I used to fill both cans. I also keep a little activated carbon and silica gel thing in there; like the kind that you get in a pill bottle to keep the pills dry. Does anyone know if these kinds of desiccants actually have adverse effects on blackpowder?
 

RocketboyG80

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jcrocket, thanks for that info. I actually have sixteen Daveyfire 28B's in my range box but since I had two Pratt ejection cans left I decided to use those. I think I'll stick with the Daveyfires from now on, just to be on the safe side.
 

Skyhigh

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On my level 2 attempts...... twice I had ematch failures and was also using a Mawd altimeter and dual ematches. The third attempt I only used 1 ematch per ejection canister and everything went off without a hitch. Strangely though the first attempt only the main fired and on the second attempt only the drogue fired. Can't to this day figure why or how but ever since I've used only single ematches per load and no problems since.
 
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