Interesting Magnum Flight

[n3tjm]

Some of you may have heard on the Oct 2nd CMASS thread that my Magnum had an interesting flight. (All flight pictures taken by n3tjm)

The Magnum was loaded with a central AMW J357 and two G64's.

Ignition... only the G64's are thrusting.... However, the blast plattern on the deflector afterwards did show that the J did burst out some energy becuase it left a nice aluminum deposit,

I am amazed that the 2 G's can lift this beast.

The motors are running out of umph.... Where is that J? Come on J!

The J ignites just before the G's burn out.

The flight now is arching towards the woods, it made it to 1800 ft, dual deploy performed as designed, and landed in a tree. I was able to recover it after the launch... the 35' pole could just reach it. Some damage to the fwd end of the body tube from twisting the cord around the pole, but I was planning to shorten the tube by a few inches anyway.

The Flight was interesting, and was a little scary... I am glad that J kicked in when it did... I am sticking to Super Tiger to do my ground starts... those motors at least don't chuff.... at least I never seen one chuff. The video is awesome, I will have that posted soon.

 

[Stymye]

grease on the grain?






lol J/K
awesome flight !

 

[Donaldsrockets]

Wow!!!

Great pics Doug.

Too bad that all three of them didn't light at once but at least you got everything back in one piece.

The J357 flame looks like that of a Blue Thunder, just white.

Wish I could have seen it in person.

 

[marvSRG]

Sweet, Doug. Athough not perfect, that probably made for quite an unique airstarting effect. I've done that on a smaller scale with 3 C's and a center F24....not near the scale or coolness of yours, I'm sure, but man, that big center white motor lighting up as the rocket slowly ascends makes for a sweet effect. Nice pics, and interesting and cool looking flight!

 

[r1dermon]

that thing was awesome. too bad the J didnt kick in, i would've liked to see it go straight up. but even still, that thing sounded like a full sized jet taking off...kudos doug, not how you planned it, but still very impressive to see.

 

[Rocketjunkie]

In general, smaller diameter motors will light faster than larger. A big, hot igniter in the large motor will help.

 

[BobH48]

That was an awsome flight. It was pretty straight and just started to arc a little when the J kicked in.

I saw it go in to the edge of the woods so I am glad to hear you got it back with only minor damage, Doug.

Just one of several impressive flights for Doug that day.

 

[wickball]

I'm curious about your 35 foot pole for future reference. I had a small rocket in a tree once, went to Lowes, looked around, 3-10 foot lengths of PVC was too flimsy, had to give up on the rocket. Please tell me more about the pole you used.

wick

 

[rocketdad0934]

the pole is a linemans pole used by the electric co to clear ice and other debres from the lines I don't know how or who got the thing but it is nice to have at the launches I've seen it used a couple of times

 

[rocketsonly]

Originally posted by WICKBALL
I'm curious about your 35 foot pole for future reference. I had a small rocket in a tree once, went to Lowes, looked around, 3-10 foot lengths of PVC was too flimsy, had to give up on the rocket. Please tell me more about the pole you used.

wick

One of the light weight aluminum extension rods used for changing light bulbs in tall places works very well! I'm pretty sure the tree my science fair rocket (carrying an altimeter) was around 30 feet, if not more, one of the maintainance guys at my school had to use a man lift.

Just find a 3 pronged object (2 prongs might work better) and duct tape it to the top of the rod. When you get the rod to the correct height, just twist the prings around the shock cord, if possible. Give it a good yank, and down she comes!

 

[JDcluster]

I had a flight similar to that in my Magnum some time ago( 1997 I think).
I had 2 F 101 SS as the outboards & a central Kosdon I 500 all to be ground started.

What actually happened very dramtic:
The F's lifted it off the pad & pushed it to about 50 to 75ft in the air, where it basiclly stopped & just as it was about to fall back the I kick in.

The altimeter did it's job & everything was ok
Alt. was about 1100 ft

The best & worst flight I've ever had.



JD

Originally posted by n3tjm
Some of you may have heard on the Oct 2nd CMASS thread that my Magnum had an interesting flight. (All flight pictures taken by n3tjm)

 

[billspad]

Originally posted by WICKBALL
I'm curious about your 35 foot pole for future reference. I had a small rocket in a tree once, went to Lowes, looked around, 3-10 foot lengths of PVC was too flimsy, had to give up on the rocket. Please tell me more about the pole you used.

wick

It's called a hot line telescopic stick used by power companies. I believe we paid about $300 for it 10 years ago.

https://www.hubbellpowersystems.com/powertest/literature_library/pdfs4lib/Chance-Hotline/07-9605.pdf

 

[n3tjm]

A very good investment.

 

[wickball]

Thanks for the info on the pole, guys.

wick

 

[jcsalem]

I bought a 20+' aluminum telescoping pole for around $30 a few years ago. Unfortunately, the small company that made it (somewhere in the midwest) now seems to be out of business. It has various attachments (e.g., dust mop) and was designed for cleaning high nooks and crannies.

You might try looking for telescoping poles from companies that sell supplies to window cleaners.

When I've lost them higher than that pole reaches, I duct tape on a 15' telescoping pole for opening skylights and then my neighbor's skylight pole and then a 10' wooden clothes rod and finally (did this once) a 10' long sturdy tree branch. With this "full" configuration, I was able to reach over 50' high and recover the rocket. However, the pole was nearly impossible to control when it got to that height. Fortunately, since I was in the middle of the woods, the other trees around prevented the pole from completely toppling over as I was swinging it madly amongst the branches.

The CMASS pole is very sturdy and doesn't bend much. But $300 is a lot to pay unless you're a decent sized club.

-- Jim

 

[Rocketjunkie]

Originally posted by jcsalem
The CMASS pole is very sturdy and doesn't bend much. But $300 is a lot to pay unless you're a decent sized club.

Most of that $300 is certification for use around live power lines. I don't know if uncertified ones are available.

 

[n3tjm]

Here are the videos from its flight:

https://n3tjm.crosswinds.net/Oct22004/Flight_of_the_Magnum.mpg - Prep, Launch, and Recovery of my Magnum. AWESOME LAUNCH!!! 11.1 MB.
https://n3tjm.crosswinds.net/Oct22004/12_Dougs_2G64_J357_Magnum.mpg - Just the launch and recovery. 3.76 MB

 

[billspad]

Originally posted by Rocketjunkie
Most of that $300 is certification for use around live power lines. I don't know if uncertified ones are available.

I'm sure some of it is but I doubt it's most of the $300. Price up 7 five foor lengths of fiberglass airframe from 3" down to 1" diameter. It's essentially the same thing.

 

[Dr. Don]

I picked up one of the 40' poles last year.
WW Grainger usually stocks different lengths. But they are a bit pricey. I found a re-conditioned one at a local tool supply outfit called Shannon O,Tools for about $225. I can justify it as a legit business expense since I can use it as an electrician!
I bring it to the St. Louis Club launches and offer aid
to all who become prey to the rocket eating trees.
Feel free to attend our Ellsberry launch with no fear of
feeding your bird to a woody beast! Dr Don

 

[billspad]

Originally posted by Dr. Don
I picked up one of the 40' poles last year.
WW Grainger usually stocks different lengths. But they are a bit pricey. I found a re-conditioned one at a local tool supply outfit called Shannon O,Tools for about $225. I can justify it as a legit business expense since I can use it as an electrician!
I bring it to the St. Louis Club launches and offer aid
to all who become prey to the rocket eating trees.
Feel free to attend our Ellsberry launch with no fear of
feeding your bird to a woody beast! Dr Don

Pricey is an understatement. I just checked out their website and saw a really nice carrying case for the hot stick. It's only $460! And it's just PVC.

 

[BlueNinja]

Nice flight Doug! The flame looks cool as the G's are burning out.




Bill- You could make your own PVC case for, oh, $10-20.

 

[Dr. Don]

Hey Doug!
I got sidetracked responding to the "stick" thing......
I have been working on my magnum for about a year and
hope to have it ready to fly at Ellsberry in a couple of weeks!
I have been warned over and over NOT to try to start all
3 motors on the pad. So I have been trying to wait until I can rig the bird for air starting the outboards. I have a nice little
K-550 set aside for my maiden voyage!
Here's a pic of the bit of extra "beefing" I added to the motor
mount assembly to handle longer 29s:

 

[billspad]

Originally posted by Blue_Ninja_150
Nice flight Doug! The flame looks cool as the G's are burning out.




Bill- You could make your own PVC case for, oh, $10-20.

I could make it for a lot less than that, I'm a plumber. Most of the launch equipment that CMASS has has plumbing parts in it.

 

[n3tjm]

Today I bought a scale to weigh my magnum. It is about 192 oz with out motors, charges, and without the Pet2 Timer Unit installed. Here is some sims using the AMW 54/1050 motor.

J357 - 2380 ft
J370 - 2510 ft
J400 - 2760 ft
J450 - 2700 ft
J480 - 3020 ft.

Usually the actual altitudes I get are lower than that.

But almost 3000 with the J480 . I am all for that motor . I have an order for another J357 and a J480 with AMW

I really do like the AMW motor... impressive powerm ranges, longer burns for most of the loads... gotta love it .

Here is the detailed results from the sims. Very interesting:

Launch guide length is 96.000 In. Default minimum velocity for stable flight: 43.999 ft / s (I usually use 32 ft a sec min)

J357 White Wolf
Velocity at launch guide departure: 43.987 ft / s
The launch guide was cleared at : 0.394 Seconds
Minimum velocity for stable flight reached at: 97.250 In.
Maximum acceleration: Vert: 165.855 Ft./s/s
Maximum velocity: Vert: 395.706 ft / s
Maximum altitude: 2379.810 Ft.
Time to burnout: 2.950 Sec.
Time to apogee: 12.991 Sec.
Optimal ejection delay: 10.041 Sec.

J370 Green Gorilla
Velocity at launch guide departure: 46.076 ft / s
The launch guide was cleared at : 0.402 Seconds
Minimum velocity for stable flight reached at: 89.212 In.
Maximum acceleration: Vert: 196.222 Ft./s/s
Maximum velocity: Vert: 412.298 ft / s
Maximum altitude: 2508.503 Ft.
Time to burnout: 2.820 Sec.
Time to apogee: 13.126 Sec.
Optimal ejection delay: 10.306 Sec.

J400 Red Rhino
Velocity at launch guide departure: 49.965 ft / s
The launch guide was cleared at : 0.369 Seconds
Minimum velocity for stable flight reached at: 76.722 In.
Maximum acceleration: Vert: 201.097 Ft./s/s
Maximum velocity: Vert: 447.749 ft / s
Maximum altitude: 2755.550 Ft.
Time to burnout: 2.660 Sec.
Time to apogee: 13.573 Sec.
Optimal ejection delay: 10.913 Sec.

J450 Super Tiger
Velocity at launch guide departure: 52.204 ft / s
The launch guide was cleared at : 0.312 Seconds
Minimum velocity for stable flight reached at: 68.441 In.
Maximum acceleration: Vert: 248.565 Ft./s/s
Maximum velocity: Vert: 452.605 ft / s
Maximum altitude: 2699.931 Ft.
Time to burnout: 2.330 Sec.
Time to apogee: 13.255 Sec.
Optimal ejection delay: 10.925 Sec.

J480 Blue Baboon
Velocity at launch guide departure: 53.578 ft / s
The launch guide was cleared at : 0.330 Seconds
Minimum velocity for stable flight reached at: 66.976 In.
Maximum acceleration: Vert: 235.540 Ft./s/s
Maximum velocity: Vert: 485.820 ft / s
Maximum altitude: 3020.052 Ft.
Time to burnout: 2.490 Sec.
Time to apogee: 13.933 Sec.
Optimal ejection delay: 11.443 Sec.

 

[marvSRG]

Originally posted by n3tjm

J480 - 3020 ft.

Usually the actual altitudes I get are lower than that.

But almost 3000 with the J480 . I am all for that motor

[/B]

Ahh yes, only almost 3000 alone ....but with twin H180W or I200W airstarts? Then we're talking altitude! Cool stuff, Doug.

 

[Bill]

Originally posted by jcsalem
I bought a 20+' aluminum telescoping pole for around $30 a few years ago. Unfortunately, the small company that made it (somewhere in the midwest) now seems to be out of business. It has various attachments (e.g., dust mop) and was designed for cleaning high nooks and crannies.

You might try looking for telescoping poles from companies that sell supplies to window cleaners.

DARS members are fond of saying that "all stores can be rocket stores."

While lying in bed last night reading the Fall/Winter 2004 Amateur Electronic Supply (https://www.aesham.com) catalog, it struck me that they too have become a rocket store. AES now carries a small selection of Quest kits, motors and accessories.

But that is not why I post. They also carry a telescoping fiberglass antenna mast. Extends to 33' and collapses down to 3.8'. Weighs a mere 3.3 pounds, so a waiver is not needed to use one. Model MFJ-1910 lists for $79.99, a lot of money, but a bargain compared to a lineman's pole. It's not certified, but I will be staying away from power lines anyway.

I absolutely love printed catalogs...


Bill