Lakeroadster's F-79 Lone Wolf

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Very nice! Is the slot of the side of the nose cone for the 20mm cannon?

With four motors, gonna be a spectacular lift off.

I figured the upside down 5 was because this is the team member that spent the most time inverted.
 
Very nice! Is the slot of the side of the nose cone for the 20mm cannon?

With four motors, gonna be a spectacular lift off.

I figured the upside down 5 was because this is the team member that spent the most time inverted.

Yep... cannon ports. pew...pew pew... pew

1st launch will be 2 motors.... dual canted D12's. Simulation shows 333 ft apogee.. should make for a visually exciting flight with the lower height and the rear eject dual chutes.

Yep.... Thunderbird 5 does have it's number upside down.. T-bird trivia ;)
 
@lakeroadster One of the things you haven't shown us on the F-79 and the Hammerhead is your recovery systems. What are you using for shock cord? How are you attaching it? What size chutes do you plan on using? Inquiring minds want to know. (And if you remember where this phrase came from you too are an old fart.)
 
@lakeroadster One of the things you haven't shown us on the F-79 and the Hammerhead is your recovery systems. What are you using for shock cord? How are you attaching it? What size chutes do you plan on using? Inquiring minds want to know. (And if you remember where this phrase came from you too are an old fart.)

I am lakeroadster, and I am an old fart.... :computer:

The F-79 weighs about 19 ounces (it's a pig). It has dual 24" long 75# kevlar chords attached to the eyebolt at the back of the rocket, attached to Dual 18" Estes plastic chutes that should yield a descent rate of about 18 fps. I'll use a #7 Eagle Claw Barrel Swivel on the eyebolt. No shock chord since there's no chance of zippering.

The recovery on the Hammerhead is a bit unconventional. I'll post the information over on it's build thread.

 
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I am lakeroadster, and I am an old fart.... :computer:

The F-79 weighs about 19 ounces (it's a pig). It has dual 24" long 75# kevlar chords attached to the eyebolt at the back of the rocket, attached to Dual 18" Estes plastic chutes that should yield a descent rate of about 18 fps. I'll use a #7 Eagle Claw Barrel Swivel on the eyebolt. No shock chord since there's no chance of zippering.

The recovery on the Hammerhead is a bit unconventional. I'll post the information over on it's build thread.

Ah...so you know where that phrase came from. :) Have you ever tried to explain to a young person what a vinyl record is? It is interesting.
 
Ah...so you know where that phrase came from. :) Have you ever tried to explain to a young person what a vinyl record is? It is interesting.

We've still got our Technics turntable and a good assortment of 45's and 33 1/3's... so I'll just show them. That's back when you had to put forth some effort to enjoy some music.
 
The "Circle of Friends" is so handy. It allows optimal angles to place glue fillets "into position".
We used to have one of these, but the "people" are made of wood. It was carved form one chunk of wood, yet the "people" are woven together holding hands, but they also free to move. It's kind of collapsible. Hard to explain, but now the question is where did it go and can I use it for this same purpose? LOL
 
We used to have one of these, but the "people" are made of wood. It was carved form one chunk of wood, yet the "people" are woven together holding hands, but they also free to move. It's kind of collapsible. Hard to explain, but now the question is where did it go and can I use it for this same purpose? LOL

Ours is a pottery piece.
 
I've been updating all my previous rocket designs to Open Rocket Model version 22.02.beta.01. And now when I open the file, it has the correct number of pods / fins. Technology marches on!

This simulation model varies pretty dramatically from the actual as built rocket geometry (no canted motor, straight wing profile, blunt pod closures, etc.). Looks like the D12-5's should work fine as long as they both fire. I'm wondering if maybe D12-3's would be wise for the first flight? That way if the rocket's performance is sub-par it might have a chance to get the laundry out before it lawn darts?

I hope to launch this rocket this spring. After the rocket is built... I pretty much loose interest and move onto the next design. :dontknow:

2022-03-29 F-79 Dual D-12 Open Rocket Flight Plot.jpg 2022-03-29 F-79 Open Rocket Simulation.jpg
 
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I've been updating all my previous rocket designs to Open Rocket Model version 22.02.beta.01. And now when I open the file, it has the correct number of pods / fins. Technology marches on!

This simulation model varies pretty dramatically from the actual as built rocket geometry (no canted motor, straight wing profile, blunt pod closures, etc.). Looks like the D12-5's should work fine as long as they both fire. I'm wondering if maybe D12-3's would be wise for the first flight? That way if the rocket's performance is sub-par it might have a chance to get the laundry out before it lawn darts?

I hope to launch this rocket this spring. After the rocket is built... I pretty much loose interest and move onto the next design. :dontknow:

Update:
  • I ran the sim for D12-3's (screenshot below)... they make the most sense for the first flight.
View attachment 511930
Always wise on a first flight to use a shorter delay on high drag rocket planes that some may say are on the "piggy" side.
 
may be too late for flight today.

If I got this right, this is going to eject chutes out the rear and come down nose first. Looks like you have a grassy/weedy field, so you are probably good. But nose down recoveries can be tough on painted pointy nose cones. Consider putting a bit of masking tape (or I have used a section of a nerf dart, it is a bit draggy and may mess up a flight of a rocket which is otherwise marginally stable) on the tip of the cone just before flight.
 
Launch Report

We launched the F-79 today on (2) D-12 Estes black powder motors. This rocket has (2) rear eject 18" Estes Parachutes.

There was some slight weathercocking, but a stable flight was witnessed. Unfortunately, I didn't get any video or photos of motor ignition, or of the powered flight.
I did however shoot video of the rocket just past apogee, of the rocket shredding the Estes chutes and then it going ballistic. From my perspective it appeared it was a "Ford Ranger seeking missile". Quite the pucker factor.

The rocket lawn darted, 151 feet west of the launch pad. This rocket features full-length coupler / body tube construction, and a hardwood nose cone. Amazingly the rocket only sustained some awesome "high speed earth induced" patina. No structural damage.

What I learned:
  1. Design the rocket so nylon chutes can be used. I don't think the recovery bays on this rocket can accommodate dual 18" nylon chutes.
  2. I should have used D12-3's, instead of D12-5's. Then the laundry would have been spit out sooner.



000.JPG001 Launch- Apogee.jpg002 Launch - 1st Ejection Charge.jpg002 Launch - 2nd Ejection Charge.jpg003 Launch - Parachute BIllows.jpg004 Launch - Parachute Rips Loose From Shroud Lines.jpg005 - Launch - 2nd Chute visible  but not opening.jpg006 - Launch - Pre Lawn Dart.jpg007 Lawn Dart.JPG011.JPG
 
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Launch Report

We launched the F-79 today on (2) D-12 Estes black powder motors. This rocket has (2) rear eject 18" Estes Parachutes.

The rocket lawn darted. This rocket features full-length coupler / body tube construction, and a hardwood nose cone. Amazingly the rocket only sustained some awesome "high speed earth induced" patina. No structural damage.
The nose cone doesn't look too bad. A little sanding & paint and it will look new.

I've pretty much given up on plastic parachutes and I have switched to lightweight nylon. I really like the chutes from Top Flight Recovery.

https://topflightrecoveryllc.homestead.com/thinmil.html
 
Is that black masking tape holding the parachutes in place during launch? Or do you remove it prior to launch? Curious if parachutes would fall out if not contained somehow.
 
Is that black masking tape holding the parachutes in place during launch? Or do you remove it prior to launch? Curious if parachutes would fall out if not contained somehow.

Yes, the chutes would fall out. I used the fingertips from a black nitril glove and stretched it over the BT-50 body tubes. They pop right off at ejection.
 
Thin mil nylon and small shroud lines will fit nearly anywhere a plastic chute fits.

Hmm... I bought my nylon chutes from BMS, and per Bill "They are made by "Top Flight" in Wisconsin. Hand cut & sewn in the owner's house".

On the nylon chutes I have, the double stitched hem all the way around the edge is pretty bulky.
 
Launch Report

We launched the F-79 today on (2) D-12 Estes black powder motors. This rocket has (2) rear eject 18" Estes Parachutes.

There was some slight weathercocking, but a stable flight was witnessed. Unfortunately, I didn't get any video or photos of motor ignition, or of the powered flight.
I did however shoot video of the rocket just past apogee, of the rocket shredding the Estes chutes and then it going ballistic. From my perspective it appeared it was a "Ford Ranger seeking missile". Quite the pucker factor.

The rocket lawn darted. This rocket features full-length coupler / body tube construction, and a hardwood nose cone. Amazingly the rocket only sustained some awesome "high speed earth induced" patina. No structural damage.

What I learned:
  1. Design the rocket so nylon chutes can be used. I don't think the recovery bays on this rocket can accommodate dual 18" nylon chutes.
  2. I should have used D12-3's, instead of D12-5's. Then the laundry would have been spit out sooner.



View attachment 526604View attachment 526605View attachment 526606View attachment 526607View attachment 526608View attachment 526609View attachment 526610View attachment 526611View attachment 526612View attachment 526613

As far as lawn darts go, this one is an A+
 
Hmm... I bought my nylon chutes from BMS, and per Bill "They are made by "Top Flight" in Wisconsin. Hand cut & sewn in the owner's house".

On the nylon chutes I have, the double stitched hem all the way around the edge is pretty bulky.
I’ll poke around my chute stash and see what I have. I don’t think I have an 18” but it’s possible. What are the dimensions of your recovery bay?
 
I’ll poke around my chute stash and see what I have. I don’t think I have an 18” but it’s possible. What are the dimensions of your recovery bay?

Thanks,

Each "Side Pod" is made from BT-50 tubing, 0.99" I.D.
Chute/ Wadding recovery area in the tube is about 7-1/2" long. If I could have at least 1" for wadding, let's say 6-1/2" long.

I could make some modifications if need be.

F79 Dwg Rev 10 Sht 11 of 16 .jpg
 
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