Delta IV

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Delta-IV

Well-Known Member
Joined
Jan 18, 2009
Messages
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Location
Mount Dora, Florida
As you can tell by my avatar, I am really into Delta IV's both professionally and as a hobby.

I was finally able to get that transfer back in 2005 that I had been wanting for years, well decades. Shortly after arriving here, I also got back into model rockets and found a great club in the Orlando area (ROCK NAR#622).

I re-started my rocketry hobby with the Estes Mercury-Redstone and then started to dream about making and flying my own scale models.

I started with a semi-scale 18mm Delta IV Medium as a prototype for even a more detailed model.

DIV-Med-4-18mm-Prototype.jpg

DIV-Med-4+2-18mm-Prototype.jpg

DIV-Med-5-18mm-Prototype.jpg
 
Then I started planning on a Delta-IV Heavy, I used the prototype Medium and added two captive strap-on boosters.

The first flight was almost a complete disaster. I didn't know about the CP/CG relationship and the rocket was very aft heavy.

Here is when the Rocketry Forum became my friend. So many here gave me the knowledge to overcome my issue and I added 2 ounces of ballast and then the prototype flew perfectly.

DIV-HVY-18mm-Prototype.jpg
 
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I increased the motor size to 24mm and really put some detail into the rocket. I used powerpoint to mimic the shaved spray-on foam of the LH2 and LOX tanks and made a mold of the tailcone with all of the indentations using a vacumn forming table.

This time I built 3 rockets simultaneously, a Medium 4-meter fairing, a Medium 5 meter fairing and the Heavy. I had found "Sandman" here on the forum and Gordon built me some great nose cones!

The 4 meter was used for my very first APCP flight. That got me hooked wanting to get into MPR/HPR.

I "mastered" ;) separating the SRM's and the two strap-ons on the heavy. This is still the neatest thing about these rockets.

I had to retire the 4 meter after a CATO, still mostly intact, just a bit of burn damage. I retired and gave the 5 meter to a friend who displays it at work. The heavy is still flying and it flew it's 19th flight last Saturday.

DIV-Med-4+2-24mm.jpg

DIV-Med-4-24mm-APCP.jpg

DIV-Med-5+2-24mm-Liftoff.jpg

DIV-Med-5+2-24mm-SRM-Sep.jpg
 
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Next it was onto High Power.

I built a bare scale of the Medium and launched it on its maiden flight with a 38mm G61W.

I then added the detail to this 5+ foot high rocket. I used real foam on the tanks and made the motor mount to be able to change out the lexan fins if one should break.

I recently added 2 SRMs to put it into the GOES-O configuration. The real one (GOES-O) looks like a late June launch at the earliest.

My plan is to launch mine with 29mm F40W's in the 2 SRMs and a H123W in the core this Saturday.

DIV-Med-38mm.jpg

DIV-Med-4+2-38mm.jpg

DIV-Med-4+2-38mm-Pre-Flight.jpg

DIV-Med-4+2-38mm-Liftoff.jpg
 
What a magnificent series of rockets!
 
Nice work, I got to get out to R-O-C-K and see you work up close. NEFAR is a bit of a drive though.
 
Say, we never saw a closup of the funky tailcone you were going to make from my "master".

How did that turn out?
 
Say, we never saw a closup of the funky tailcone you were going to make from my "master".

How did that turn out?

Well actually very well...see below

The master carved and added detail is on the left, the mold in blue and a rigid foam 38mm copy.
 

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JAL3 said:
What a magnificent series of rockets!
mjennings said:
Nice work, I got to get out to R-O-C-K and see you work up close. NEFAR is a bit of a drive though.
nice work and launch pictures..:)

Thanks, and if all goes well tomorrow I'll have more with my HPR 38mm Delta IV Medium with 2 active SRMs at NEFAR.
 
I would love to see that in person.............but since I'm about 1,000 miles away, I'll settle for pictures - lots of pictures! Right guys?? :cheers:
 
I would love to see that in person.............but since I'm about 1,000 miles away, I'll settle for pictures - lots of pictures! Right guys?? :cheers:

I'm planning to get up early tomorrow to drive 70 miles to the NEFAR launch just to get photos of Carl's rocket! :)

Carl's web site is at:

https://www.delta-iv-rockets.com/

I have many photos of his rockets on PayloadBay.com at:

https://www.payloadbay.com/gallery/v/other/delta/

Also, Ryan, a ROCK member and a skilled crafter of scale rockets himself, takes photos of Carl's flights. He uploads them to https://picasaweb.google.com/ryrego.

-- Roger
 
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I would love to see that in person.............but since I'm about 1,000 miles away, I'll settle for pictures - lots of pictures! Right guys?? :cheers:
OK, here's some of my shots of Carl's Delta IV. I'll let him fill in the details
(although there's a hint in one of the pics)...

CarlCampbell_DeltaIV_preflight_sm.jpg

CarlCampbell_DeltaIV_glamour_sm.jpg

CarlCampbell_DeltaIV_liftoff_sm.jpg
 
OK, here's some of my shots of Carl's Delta IV. I'll let him fill in the details
(although there's a hint in one of the pics)...

Thanks Brian....I think :confused:

Prior to the 7th flight of my 38mm Delta IV Medium, the first with active SRM's my main worry was on getting the smaller 29mm F40's to ignite as fast as the 38mm H123. I bought and dipped my own igniters and test flew them 3 times prior to this launch.

I prepped the F40 motors with a bit of pryrogen on the grain slot as was recommended. I used the igniter that came with the H123. That may have been the critical mistake I made today. The 2 F40's in the SRM ignited just fine, the H123 did not even lite the igniter..so in the photos below you'll see the ramifications of that critical event.

To go back 8 hours, I'd have installed one of my dipped igniters into that H123 and would had checked the resistance of the igniters. My meter isn't too acurate, but the AT igniters were low but twice the resistance.

I need to get a better meter to better pair them in the future as well.

FLT-7-Post-Flight-a.jpg

FLT-7-Post-Flight-b.jpg
 
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Oooooh.............really sorry to see that. I hope the damage isn't too much to prevent a repair. :y:
 
I just completed removal of the damaged top end. should be able to fly it again in a couple of months. This may delay my Sheri's Mercury Redstone build a bit.

Correction, upon further examination, the motor tube about half way down the length of the remaining sustainer tube has a buckle in it and has been weakened.

I "totaled" the darn thing, at least I have all the parts needed for a complete re-build as my next effort was for a 38mm Heavy version, that will now be delayed.

On a bright note, now I'll be able to implement dual recoverery in this re-build. I had to walk quite a ways in recovering this single deployment bird a few times..
 
Sorry about the prang... really hate to see a beautiful rocket like that crash... Looking forward to the rebuild pics!

Say, I've got a question for you... In the second pic on Post 5 above, the indoor shot, you have some WAY cool posters on the wall there behind your rocket... any idea where I could get some of those?? They look awesome!

Thanks! OL JR :)
 
Sorry bout the crash, JR I don't know if those are posters are publicly available, I inherited 2 similar ones when I started working at KSC, but they are the old blue skin Delta IV not in the orange foam.
 
Sorry bout the crash, JR I don't know if those are posters are publicly available, I inherited 2 similar ones when I started working at KSC, but they are the old blue skin Delta IV not in the orange foam.

We get some extra copies ever once in a blue moon, mostly for Open Houses, etc. though.

We'll if we didn't crash em every so often we'd run out of storage space...I guess I can think of that as solace for my pain. :(

The re-build will be a better rocket, with lessons learned and I won't make that same mistake ever again when I cluster APCP.
 
The re-build will be a better rocket, with lessons learned and I won't make that same mistake ever again when I cluster APCP.

Spoken like a true Engineer, I learned more from a single failure than I could have from a dozen successes.
 
Sooo, what's your secret for successful BP clustering with strapons...hehehe? I've built one for my boy that has two 18mm side pods a central 18mm booster to a 24mm sustainer. 1st flight was perfect. Second flight only lit the booster and one side pod. Rocket took off to about 75' and started to weathercock severely. It staged horizontal and pranged under power about 800' out.

This is not my first bp cluster by any means but I am no pro. I used regular estes igniters (all in like condition and roughly same amount of pyrogen on them) with a 12v system that has only failed to light a three motor cluster on one occassion.

Tips and tricks you encorporate? Thanks
 
In my BP Delta Series here are my results:

Delta IV Medium Prototype (18mm):
2 Cluster Flights
- 1 Flight 1 strap-on did not fire

Delta IV Heavy Prototype (18mm):
5 Cluster Flights
- All good

Delta IV Medium (24mm - 18mm):
10 Cluster Flights
- 2 Flights 1 strap-on did not ignite

Delta IV Heavy (24mm):
19 Cluster Flights
- 3 Flights 1 strap-on did not ignite
- 1 Flight 1 strap-on was late in igniting
- 1 Flight Central did not ignite

Mainly my tips and lessons learned are
1. Make sure the Estes igniters are not touching together just below the pryrogen
2. Inspect, replace or clean clip contacts before use
3. Make sure battery is charged.
4. Don't even think "...now did I forget something" just as the LCO is counting to "two...one"'
 
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Sooo, what's your secret for successful BP clustering with strapons...hehehe? I've built one for my boy that has two 18mm side pods a central 18mm booster to a 24mm sustainer. 1st flight was perfect. Second flight only lit the booster and one side pod. Rocket took off to about 75' and started to weathercock severely. It staged horizontal and pranged under power about 800' out.

This is not my first bp cluster by any means but I am no pro. I used regular estes igniters (all in like condition and roughly same amount of pyrogen on them) with a 12v system that has only failed to light a three motor cluster on one occassion.

Tips and tricks you encorporate? Thanks

I'd recommend using Quest Q2G2 ignitors instead of Estes for clustering-- their firing amperage requirements are MUCH lower and they have long flexible leads which can be twisted together for virtually foolproof connections without clip whips, which, if the clips are dirty, can fail to pass current to certain ignitors.

Our club members have been QUITE impressed with them so far! OL JR :)
 
Those deltas were amazing. I look forward to your rebuild :)
:cheers:
fred
 
Sorry for your loss, that looked like a great rocket.

I've learned a few things about clustering APCP over the flights of my Titan, here are a few.

1. If you can, hook up each motor's igniter to a different pad instead of wiring all of them to the same clips, you can check the continuity of each igniter that way. Have the LCO light all of the igniters drag-race style if the system is powerful enough.

2. Use Magnalite, the stuff is amazing, any amount of it will light any motor.

3. Never use igniters that barely fit in the motor core, the igniters will build up pressure in the motor and spit themselves out before they light the propellant. The only time I've done this is with E-Matches and Magnalite, both motors chuffed and both didn't light.
 
I was asked a few months ago wether I could build a display model based on my flying 24mm Delta-IV Heavy. When I lawn darted my 38mm Medium (I cryed a bit on that one), I decided to do it before starting the re-build.

Here is the almost finished product. I have learned a great deal of respect for those who model to such detail.

However, I am starting to get that uneasy feeling about giving away my child.....

DIV-Heavy Display.jpg
 
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