7.5" Titan II Missile 2 Versions

Here is the second flight video with recovery.

https://www.youtube.com/watch?v=Gud941qfsA0&feature=youtu.be

burkefj said:

it blew the forward end right through/past the new delay unit...

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Sorry to hear this, beautiful rocket! I'm not certain what the failure looked like: the delay unit was blown off, the retaining ring was blown off, flame just shot out of the delay unit? What's the condition of the motor case? It doesn't speak well for the reliability of RMS-EZ in any event.

Here are some flight pictures.

Talked to Karl Baumann, and he will replace the motor and ring, said that every once in a a while there is a small void in the epoxy or tube that holds the delay and that the flame front finds its way forward, and it appears this is what happened. He confirmed that I could use a long burn plugged closure in these motors and avoid any front end parts completely, since I run redundant appogee I really don't need motor backup anyway, I'll probably do this in general.

Frank

Very spectacular launch. Well done, very impressive build.

Had a perfect flight today at fire in the sky in Washington on a j-510, dead straight, good flame, its the perfect motor, used the plugged closure, makes assembly and cleanup very quick.

Frank

Wow! That's a spectacular mishap! Sorry to hear about that, but I'm glad the rocket was not badly damaged, and you were able to repair it. Now you not only have an awesome rocket, but you also have some amazing crash photos too!

EDIT: Oops. Didn't read the second page of posts before replying. Sounds like you had a second day of launch success since the first flight. Congratulations! That is a really cool rocket.

Yes, and I'm such a dork. While I was at the Evergreen aviation museum in Oregon several months ago, they were closing out their little sterling silver charms of the Titan II missile, so I bought two, and put them on some dog tag chains I had. I taped them to the Titan II for the J-510 flight, and gave one to my son afterward since he was nice enough to help me out and do some of the driving, and and I kept one for me. We now have matching Titan II jewelry that has "flown" on an actual Titan II(rocket, not missile).....dork mode off.....

Frank

Here is a new set of photos from Gary Goncher.

Frank

Another great shot from Gary

Here is the perfect second flight later in the day, same J570 motor, but standard forward delay element/closure.

Great series of photos!

Congratulations, Frank! The video for the second flight looks terrific. I am amazed that you could fly the model successfully in the same day after such a fiery first flight.

Very cool model and flights. It is amazing how you simulated both the successful and unsuccessful early Titan flights. That must have got you more scale flight points - you meant to do that for all the scale guys. Just like the good old NASA films of all the early failures. It is always good when such a spectacular fail results in easily repairable damage.

It was good construction, and a lot of luck in how the flame missed the chutes and the bodies didn't slam into each other....

Daddyisabar said:

Very cool model and flights. It is amazing how you simulated both the successful and unsuccessful early Titan flights. That must have got you more scale flight points - you meant to do that for all the scale guys. Just like the good old NASA films of all the early failures. It is always good when such a spectacular fail results in easily repairable damage.

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burkefj said:

Talked to Karl Baumann, and he will replace the motor and ring, said that every once in a a while there is a small void in the epoxy or tube that holds the delay and that the flame front finds its way forward, and it appears this is what happened. He confirmed that I could use a long burn plugged closure in these motors and avoid any front end parts completely, since I run redundant appogee I really don't need motor backup anyway, I'll probably do this in general.

Frank

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Great to see your Titan II didn't suffer too much damage, your lucky, lots of others have not been as lucky. Well it's good to know that Aerotech only screws up some of the RMS-EZ loads. Nice of them to replace the reload, they don't give a crap about the destruction or damage to our rockets. I've seen to many of these EZ loads blowing their tops.

I'd like to thank aerotech and mike at bay area rocketry for getting me a replacement motor in timely fashion.

One of my Nephews from France is staying with us so we took him to NXRS yesterday and I launched my titan II on a J-510, perfectly dead straight flight, unfortunately wind blew it back toward the flight line and the upper half nearly took out my daughter, she had to scramble out of her folding chair as it landed....got the spot landing award and no harm done...I'm wearing my new apron for rocket preparation brought by my Nephew with the La Rochelle Rugby team logo....It will help save my pants since I seem to ruin them wiping my hands on them during launches...Nephew Julien on the right, Son Max on the left...The launch tower we used added a little coolness to the photo.

Cool flights, glad you are having fun.

I made the title Titan II Twins(but not a gemini) becuase I'm also going to do a lightweight version of my Titan II at the same scale as my first version. Here is the second half of the build thread.

From my large Atlas missile I just finished I had some 3/32" clear polycarbonate leftover so I thought it might be light enough to do clear fins with a foam superstructure and make a rocket that could fly 29mm I-200's to around 1000 feet. My problem is that the fins will probably still be 15 ounces, which is quite heavy for the light structure. I'll have to lighten the root tabs with holes.

To support the fins, I'm thinking of building some hardwood guide rails in the rear thrust plate to support landing loads/flex and maybe do a lightened CR with locating slots on the forward end as well.

The front/nose will be built up foam around the 4" by 13" parachute bay, with the 29mm stuffer tube going the full length as a spine, and altimeter near the top firing the ejection charges.

Finish will be monokote trim for the silver, the foam skin is naturally white and I've got the markings on order through Stickershock.

Main body 60" long, nose 13", overall length about 78" long.

I've found some kids plastic cups for nozzles, and some styrfoam balls for the front of the nozzles and the nose.

Stay tuned.

Here is a quick rocksim, with weights for components estimated, altitude approx 1100' on an I-200. Fins came out right on my estimate with lightening holes at 15 oz for all four, they seem stiff enough. I didn't model each foam centering ring at 6" spacing, and just lumped the weight of that into the weight of the tube with an override. Ejectable nose conical section will be approx 4" by 5" with a 2.75-3" styrofoam ball nose. For this version I'm planning on using a lexan plate around the motor tube, supported by carbon rods into the thrust plate. the plastic cup "nozzles" will attach to this lexan plate with screws and the landing load will transfer to the carbon rods.

The lamp fixtures I used for the original nozzles were a bit soft, but found some stainless jiggers on sale, they were much heavier duty than my original lamp fixtures and installed them today on the heavy version, they look pretty good, the lines for the measures give a little detail.....I know they aren't scale, but I seem to have more fun trying to find something that is close without having to do a bunch of work, let's call it "lazy".....the carriage bolts actually take most of the landing load, which is why they extend down behind the nozzles, but in flight you don't see them. You can use them to measure our your "apres flight" cocktails....and alcohol was a rocket fuel.....so they are alcohol containers...they looked good enough I'll use those for the foam version as well.

Back to the lightweight version. Went through all my scraps today, found enough 3/32" lexan to do the fins, cut one out with lightening holes for the root. I had one 1/4" centering ring that was cut for a 7.5" bulkhead, used that for my template and cut one of out of my remaining 3/32" ply for the thrust plate. The 1/4" one I cut lightening holes and will be the forward plate. I also made a short plate that will go up forward and will have the rail button attached. I found some 1/4" square basswood and used that to make slots to hold the clear fins. I wanted to do this so that any landing stress will be confined to the plates and the slots and not the foam structure. Hopefully this works ok. It meant I didn't have to make a fin box out of foam or ply and was much lighter.

I found a couple of centering rings for the forward parachute bay, and installed the eye bolt. I also made a plate for the base of the cone, and put the eye bolt in place. At the craft store I found a hardwood 2.5" ball that I turned on my drill press to make a shoulder. the foam transition will sit into this shoulder and will give a nice hard end for landing. I'll put a carbon rod down the middle of it and tie it to the base plate. the hardwood nose weighs 3 oz and will probably be needed for balast anyway, any other balast can to on the base of this and around the carbon rod. The rod will tie it to the base plate and recovery eye bolt.


Well, that's it for now till I get the parachute bay tube and 29mm tube, and my foam order hasn't come in yet.

Frank

Looking good! Dude, where do you store all those big rockets?

I have some in my sons room since he is away, and the rest are in the guest room closet, the downstairs office has all my rocket gliders hanging up...i figure my guests can hang their clothes over a chair..

Here are the fins all cut and shaped with lightening holes cut with the two centering rings showing how it will all go together. Tail unit with retainer is right at 26 oz which is right on target. I also show the nose section, how the carbon rod will tie the nose and base plate together, there will be a 29mm tube in the center to act as a base to glue the foam stringers to which will support the foam skin.

Here's the weight breakdown:

Stringers 6
CR 2
Skin 4
Stuffer 5.5
ParachuteTube 5.5
Large plyCR 6.5
small ply cr 2.5
Fins 15
parachute 4.5
eye bolts 2
retainer+nozzles 3.5
altimeter 2.5
glue 2.5
wiring 1
kevlar+nomex 4.25
Nose 8
Total 75.25

burkefj said:

I have some in my sons room since he is away, and the rest are in the guest room closet, the downstairs office has all my rocket gliders hanging up...i figure my guests can hang their clothes over a chair..

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So, son goes away to college. Returns to find his room has been converted to rocket storage. :roll:

Cut the foam centering rings and notched them. For this version I went back to my original titan DynaSoar construction and did not do full width stringers with notches, I just made straight stringers and will pre-glue the centering rings on the 29mm tube, it made the creation of the stringers and installation much simpler. It's also lighter, structure as seen here is 7 oz, 54" long, 7.6" diameter.

I was at the hobby shop getting some glue, I decided I'll attach the nozzles directly to the thrust plate with blind nuts and a standoff bushing.

The motor mount will stick down between the nozzles and be black with a white stripe which will sort of look like the turbopump exhaust.

Progressing nicely.