RW Mad Dog 6 Build Thread--parts to flying on an M1939W in 46 days

[Viperfixr]

Looks familiar!

Similar purely by chance. great minds must think alike! :wink:

 

[Viperfixr]

Today I 'fit' the nosecone with a lot of sanding, trying to achieve that delicate balance between sliding on snug but not falling off when upside down. Drilled the upper airframe shear pin holes (3x 4-40 nylon screws) and the parachute bay vent hole (tiny #40 drill bit hole just below the nosecone shoulder so as to not dissipate ejection charge power). Sure isn't easy making simple holes with my drill press with such a monster rocket! Also enlarged the 4x av-bay PEM nut sized holes in the upper airframe to the outer diameter of the 10-32 screw heads--perfect, snug fit. Av-bay now screws into the upper airframe very nicely. Upper airframe stuff done.

I also ordered the drogue, heavy-duty swivels and some chute protectors from Top Flight today. Drogue is a 30" Crossfire in black and neon pink. Primary chute is a massive white/pink Rocketman I bought from Troj over a year ago, either new or like new. The primary chute will go in a 30"x30" nomex blanket, Crazy Jim 'burrito' style.

Second rail button, av-bay switch holes and lower airframe shear pin (3x 4-40 also) holes next. Then onto ground testing. Damn, I cannot wait to fly this Mad Dog. When is Oktoberfest?!

 

[Viperfixr]

A lot of progress, but not many pictures...sorry, will fix this weekend. All the 4-40 shear pin holes, av-bay switch holes, av-bay vent holes, airframe vent holes and av-bay sled to switch hole alignment is done. All of the recovery gear is now on hand and ready to be installed. Ground testing will happen this weekend, and just in time for launch a week later! Targeting either Saturday late afternoon or Sunday AM for lighting the M1939W.

 

[Viperfixr]

Probably the last update until it flies next Saturday afternoon around 3:45pm. Why then? Because my wife and daughter are coming out around 3pm and I want to make sure they get to see it launch.

After more fitting, fussing and putting the recovery gear together and setting it all up for the first time, she came in at 14 pounds for the lower section and 16.5 for the upper. So, an all-up, empty weight of 30.5 pounds seems low to me, but I am not complaining. That was without the empty motor, but everything else in. With the 14' Rocketman main and an empty motor onboard, descent rate should be a nice and sedate 15-16 fps. Perfect.

CG came in at 65.25" from the nosecone. With an M1939W in it, there's about 1.7 calibers of stability--good to go.

Rocksim guesses the altitude with the M1939W (which is really a 2% N) at 13k and change. Works for me, but I will need a waiver.

Here's what the MadDog 6 looks like all together for the first time, just before ground testing! It may not look like it, but I was tilting it back, away from the camera to help fit it all in.

Apogee ground test w/3.2grams 4f. I call this just about right. Backup at 5gr. Crazy laughter at the end compliments of my Junior L1, rocket buddy daughter Lauren.
[video=youtube;oyh7uOzRCK0]https://www.youtube.com/watch?v=oyh7uOzRCK0[/video]

Main ground test w/3.2gr 4f. I am going to up this to 3.5gr and call it good. Backup at 5gr.
[video=youtube;ljv6Pvycj4Y]https://www.youtube.com/watch?v=ljv6Pvycj4Y[/video]

Just set the altimeters with the RRC2+ as the primary at 1000' AGL and the RRC3 as the backup at apogee +2 seconds and main at 800' AGL.

Almost ready to fly!

 

[Viperfixr]

Just checked the Aerotech M1939W instructions, since I have never built/flown a 98mm motor. Good thing I checked...I have the 98/10240 motor, but not the forward seal disk (somehow)! Luckily, a quick phone call to Balsa Machining confirmed he has them in stock and will bring one to the launch. Whew! No overnight mail needed.

Big plug for Balsa Machining. Not only the best Aerotech prices from any vendor (pre-ordered), but the best customer service going.

 

[REK]

Rocket looks amazing. Great work and good luck.

 

[Onebadhawk]

Mark the build came out fantastic
and that's exactly how the flight is going to go...
Good for you...
That is one gorgeous monster of a rocket....

Teddy

 

[Viperfixr]

I don't have any pictures, but the maiden flight went just about perfectly. That Aerotech M1939W is a BEAST of a motor--just kept going and going, and the rocket clearly went supersonic at the end of the boost for nearly a second. Darned rocket weighs 50+ lbs at the pad and is a monster to maneuver, but that motor tossed the rocket like a toy.

Screen shot from mDACS RRC3 download below. Other than putting a retaining nut on the nosecone eyebolt, there is not a thing I would change. This thread in terms of building is DONE!

Next flight...perhaps LDRS??? On an N???

 

[Wayco]

I don't have any pictures, but the maiden flight went just about perfectly. That Aerotech M1939W is a BEAST of a motor--just kept going and going, and the rocket clearly went supersonic at the end of the boost for nearly a second. Darned rocket weighs 50+ lbs at the pad and is a monster to maneuver, but that motor tossed the rocket like a toy.

Screen shot from mDACS RRC3 download below. Other than putting a retaining nut on the nosecone eyebolt, there is not a thing I would change. This thread in terms of building is DONE!

Next flight...perhaps LDRS??? On an N???

Good data Mark, glad to hear you had a good flight. I flew my Red Tailed extreme on an M1550 at GHS yesterday, and had similar results.
I'm hoping to fly an N2000 on my Ultimate DS at LDRS next year, but am waiting to hear if they will let us fly anything bigger than the M that California rules permit. Maybe you have an inside line on that?

 

[blackjack2564]

Ya did it!

Made on time & flew just fine.

Outstanding!

 

[REK]

Congrats viper on the flight.

 

[Onebadhawk]

Congrats on a great flight Mark...
Well done..
I'm glad everything went perfectly...

Teddy

 

[Viperfixr]

I knew someone had to have taken some photos, and turns out that Dave Pacheco graciously shared the ones he took. All photo credit goes to him--thank you, Dave!

Loading the monster...big Thank You to Roy P, Gordon M, and new L3 John Glasswick for helping.

My Junior L1 daughter, Lauren, and me...the butterflies were fierce right then. Also, another Thank You to Roy Polmanteer for letting me use his awesome pad (that he brought all the way from AZ). Just me, but we need selfless rockteers like Roy on the TRA BoD.

Moment of truth, compliments of a fine Aerotech M1939W motor. I will fly that beast of a motor again--just beautiful.

On it's way to break the sound barrier!

 

[stealth6]

Was there and witnessed the flight - it was one of the best ones of the whole weekend.
Well done, Mark,

s6

 

[Onebadhawk]

Congratulations Mark...
Well done...
With a 98 mm mount in that beast this is only the beginning....

Teddy

 

[tmacklin]

I don't know how I managed to miss this thread but somehow I did! Terrific build and a great flight. I am especially pleased to see that one of my Guillotine fin jigs played a key part in this project and I look forward to more successful builds in the future. Thank you Mark Rose for purchasing one of my products from Apogee.

Ted