Apogee Zephyr, 1st HPR build, finished it a few months back just never got around to posting. I cant wait to see it launch.

[Dan Griffing]

I just ordered an Av-bay kit and payload tube to convert my Zephyr to dual deploy. Cant wait to stuff some big motors in it.

That’s the route I took, but there are many complex details to make dual deployment work successfully.

The amount and the packing of the BP deployment charges, and the shock cord lengths and configurations, and packing of the shock cords, chute protectors, and parachutes are extremely complex.

I also had redundant drogue and main chute ejection systems, each with different parameters.

And I did about a dozen ground tests for both the drogue and main chutes that I made high speed videos of to determine whether each deployment was working properly. The remote Bluetooth testing of the Eggtimer 6-channel Proton, with its backup drogue and main deployment modes, each with independent parameters worked quite well. Test, test, test! It’s safer to learn on the ground than when you can make changes without having to replace a crashed rocket.

I also found that an Altimeter3 mounted on the nosecone was extremely useful during testing for measuring the ejection charge acceleration to determine the optimal BP amount. The nosecone-mounted Altimeter3 was essential during the launch for collecting launch data, and using it to refine the RockSim simulation parameters.

 

[TheTank]

That’s the route I took, but there are many complex details to make dual deployment work successfully.

The amount and the packing of the BP deployment charges, and the shock cord lengths and configurations, and packing of the shock cords, chute protectors, and parachutes are extremely complex.

I also had redundant drogue and main chute ejection systems, each with different parameters.

And I did about a dozen ground tests for both the drogue and main chutes that I made high speed videos of to determine whether each deployment was working properly. The remote Bluetooth testing of the Eggtimer 6-channel Proton, with its backup drogue and main deployment modes, each with independent parameters worked quite well. Test, test, test! It’s safer to learn on the ground than when you can make changes without having to replace a crashed rocket.

I also found that an Altimeter3 mounted on the nosecone was extremely useful during testing for measuring the ejection charge acceleration to determine the optimal BP amount. The nosecone-mounted Altimeter3 was essential during the launch for collecting launch data, and using it to refine the RockSim simulation parameters.

I’ve got a several dual deploy flights under my belt at this point. Ive had great luck with Missleworks products. Converting the Zephyr will be a nice addition and allow me to fly I’s and maybe even J’s and hopefully get it back!

 

[Dan Griffing]

 

[Dan Griffing]

Here's my L2 cert Zephyr dual deployment launch with a J270W. It went 3,200 feet, came down at 47fps on a 24" X-form drogue and 13fps on a 48" Fruity Chutes Iris Ultra toroidal main.

 

[TheTank]

Here's my L2 cert Zephyr dual deployment launch with a J270W. It went 3,200 feet, came down at 47fps on a 24" X-form drogue and 13fps on a 48" Fruity Chutes Iris Ultra toroidal main.

nice! Im using an 18” drogue and bumping the main to 48” as well.

 

[Dan Griffing]

An 18" works well for a drogue on an 8-12# rocket. You just want to keep the decent below about 100fps. Too slow and it drifts too far. you also want a good rotation of the top and bottom halves below the drogue so the the main ejection won't blow the chute into the drogue and get it tangled. I also had really long Kevlar shock cords: Looped 25' recovery harness from OneBadHawk Rocketry added to the 1/2" Orange Nylon that came with the Zephyr, plus 600# swivels, and a 20' length of 2000# round Kevlar attached to the drogue.

 

[mtnmanak]

I have a couple Zephyr's in my fleet. The bright fluorescent orange one in the picture below was the one I used for my Level 1 cert flight. Figured it would be hard to lose if it was painted bright orange! I was glad I did, it ended up landing about 1/2 mile away in a farmer's field - was easy to see from the road due to the bright orange paint.

The Zephyr is a tank. I am pretty sure it could fall out of the sky without a parachute and survive with barely a scratch.

 

[Dan Griffing]

The Zephyr is a tank. I am pretty sure it could fall out of the sky without a parachute and survive with barely a scratch.

In July my Zephyr did on its sixth flight overall, and its third launch of the day, probably from its copious shock cord or flame protector-wrapped JRCR and chute packed a little too tightly. The nosecone didn’t eject, and it “lawn-darted” from about 2,000 feet.

But Zep had given me my L1 and L2 certifications before its spectacular demise.

 

[mtnmanak]

In July my Zephyr did on its sixth flight overall, and its third launch of the day, probably from its copious shock cord or flame protector-wrapped JRCR and chute packed a little too tightly. The nosecone didn’t eject, and it “lawn-darted” from about 2,000 feet.

But Zep had given me my L1 and L2 certifications before its spectacular demise.

Ouch!! But look at those 1/4" plywood fins! Still intact

 

[Dan Griffing]

Ouch!! But look at those 1/4" plywood fins! Still intact

The Apogee Zephyr through-wall 1/4” fin design is really solid.

Apogee has repeated it with its Peregrine dual deployment sister ship, and its new 54mm Katana rocket as well.

These three rockets Are solidly built and really great buys. The kits are complete, come with great instructions and are great contributions to high power rocketry.

These rockets only weakness is that they are based on cardboard airframes which eventually get squishy and weak with longterm use, impact, moisture, and high temperature BP combustion gases and residues. But that’s the trade off with having an affordable rocket kit.

 

[TheTank]

In July my Zephyr did on its sixth flight overall, and its third launch of the day, probably from its copious shock cord or flame protector-wrapped JRCR and chute packed a little too tightly. The nosecone didn’t eject, and it “lawn-darted” from about 2,000 feet.

But ZepView attachment 434757 had given me my L1 and L2 certifications before its spectacular demise.

holy fricken accordian! That nosecone! DAMN! It hit concrete?!?

 

[Dan Griffing]

holy fricken accordian! That nosecone! DAMN! It hit concrete?!?

Not concrete because the Twin Bridges, Montana BSRA site is at 5,600 feet on BLM high desert land, but it is relatively hard packed ground miles from any human development, and certainly not into a soft, plowed field.

Plenty of other “lawn darts” at this launch site needed a shovel to dig them out. The polypropylene nosecone had six pounds of rocketry cardboard, plywood and hardware behind it and driving it into the undeveloped terrain.

 

[TheTank]

Not concrete because the Twin Bridges, Montana BSRA site is at 5,600 feet on BLM high desert land, but it is relatively hard packed ground miles from any human development, and certainly not into a soft, plowed field.

Plenty of other “lawn darts” at this launch site needed a shovel to dig them out. The polypropylene nosecone had six pounds of rocketry cardboard, plywood and hardware behind it and driving it into the undeveloped terrain.

wow! We had a Wildman punisher (i believe) come in ballistic at the last launch into a sod field. Tail If the booster was 1ft down. Guy spent hours out there digging it out. Rocket was relatively undamaged though. Nose had to be 6-7’ feet down.

 

[neil_w]

View attachment 434757

That is an amazing picture.

 

[Dan Griffing]

wow! We had a Wildman punisher (i believe) come in ballistic at the last launch into a sod field. Tail If the booster was 1ft down. Guy spent hours out there digging it out. Rocket was relatively undamaged though. Nose had to be 6-7’ feet down.

View attachment 434970View attachment 434971View attachment 434969

Simply wow!

A cardboard rocket wouldn’t have this penetration capability. Instead it would dissipate its kinetic energy by flattening.

 

[JimH]

My first HP rocket arrived yesterday in the form of a Zephyr. I'm going to install an av-bay but will keep it single deploy until I get my L1. My wife said I opened the box like a kid on Christmas morning, she's right!

 

[Adam3836]

My first HP rocket arrived yesterday in the form of a Zephyr. I'm going to install an av-bay but will keep it single deploy until I get my L1. My wife said I opened the box like a kid on Christmas morning, she's right!

Great choice solid rocket, that was my L1 pick also

good luck any questions feel free to ask happy to help

 

[Dan Griffing]

My first HP rocket arrived yesterday in the form of a Zephyr. I'm going to install an av-bay but will keep it single deploy until I get my L1. My wife said I opened the box like a kid on Christmas morning, she's right!

My advice is to test, test, test.

There are many subtle and complex things to making dual deployment work that could go wrong.

I used the six-channel Eggtimer Proton both for its redundant modes of drogue and main deployment, and for its wireless WiFi features for testing each channel to determine BP amount and packing, and for every aspect of chute packing.

I hung my DD Zephyr from a stepladder with breakaway twine and masking tape to assess the deployment and recoil and did slow motion videos for over a dozen test drogue and main deployments. There are so many things that you want to learn before putting your rocket at risk with an actual dual deployment launch.

You can also use a spent DMS motor wired with an igniter and a Quantum to test the single deployment BP amount, change packing, and shock cord, chute protector, ChuteRelease, and parachute packing techniques prior to a launch. But most importantly, test, test, test. You’ll correct beginner mistakes on the ground without having to build a replacement rocket.

 

[cichlidgoob]

Same story for me...a few Tim van Milligan videos helped get me back into rocketry as well and after lots of reading and learning I am building a Zephyr for my L1 cert flight.

Although RockSim shows several motors as safe, some of them do not have the required 5 to 1 thrust to weight ratio. When I looked those motors up on thrust curve.org I realized there is sometimes/usually a huge difference between initial and average thrust. When we do the calculations for thrust-weight ratio, I presume we should use the initial thrust, not the average thrust, is that right?

 

[Adam3836]

Same story for me...a few Tim van Milligan videos helped get me back into rocketry as well and after lots of reading and learning I am building a Zephyr for my L1 cert flight.

Although RockSim shows several motors as safe, some of them do not have the required 5 to 1 thrust to weight ratio. When I looked those motors up on thrust curve.org I realized there is sometimes/usually a huge difference between initial and average thrust. When we do the calculations for thrust-weight ratio, I presume we should use the initial thrust, not the average thrust, is that right?

Check the cti H133 bs that’s the motor I used for the zephyr on my L1 it was a great motor plenty of punch off the pad and went to about 1420 feet I believe my thrust to weight was around 7.5-8.1 for my zephyr based on motor thrust and rocket weight of around 3.75lbs

 

[Gary Liming]

Here's my Zep just before its cert 1 flight. I kept it simple and used a JL chute release with an H130. Worked out, as it was fairly windy that day.

 

[Adam3836]

Here's my Zep just before its cert 1 flight. I kept it simple and used a JL chute release with an H130. Worked out, as it was fairly windy that day.

awesome looking zephyr
If your up for it and want to add a picture or 2 of your L1 flight to /hpr L1-2-3 photos thread
That would be awesome. cool thread for people to check out some cool flights and be inspired even more

 

[Donnager]

That is an amazing picture.

It is.

I lawn darted a 54mm Mach 1 Alien Interceptor from about 2200'. It became much shorter. I should have taken a picture. Kids from the colleges around doing their aerospace qualifying thought my reduced length rocket was cool after I dug it out, and I agreed.

That same Alien Interceptor will tempt fate again this weekend.

 

[donwheeler]

I have a couple Zephyr's in my fleet. The bright fluorescent orange one in the picture below was the one I used for my Level 1 cert flight. Figured it would be hard to lose if it was painted bright orange! I was glad I did, it ended up landing about 1/2 mile away in a farmer's field - was easy to see from the road due to the bright orange paint.

The Zephyr is a tank. I am pretty sure it could fall out of the sky without a parachute and survive with barely a scratch.

View attachment 434750

I am in the final stages of preparing for my L1 flight with a Zephyr, but I am confused about engines and whether or not they need casings. I am planning on using an H100 motor. First, is it powerful enough? Second, can you please explain "casings" and third, I have already installed a motor retainer, but what holds the motor in place during the propulsion stage?

 

[Adam3836]

hey there
Well there is RMS motor ….. reusable which means you have a CTI or aerotech casing and you build your motor put it in the casing secure it down with motor retainer. When the flights done pull out the leftovers of the spent motor toss it out reuse your casing for the next motor .
(Always make sure your delay is where you want it )

Now there is single use motors where no casing is required aerotech sells a lot of those
It comes ready to go just put it in the motor tube secure it with motor retainer good to go
Again make sure you pick the right delay

Also DMS motor where they are single use like the above mentioned but they can have there delay charge altered by you

best thing is to run some motors on rocksim to see what’s safe with your rocket
You need to decide how high you want your flight
Software like rock sim can show if the motor is safe for your rocket and tell you altitude
You definitely want enough thrust off the pad but just figure out how high

hope this helps



QUOTE="donwheeler, post: 2267916, member: 39193"]
I am in the final stages of preparing for my L1 flight with a Zephyr, but I am confused about engines and whether or not they need casings. I am planning on using an H100 motor. First, is it powerful enough? Second, can you please explain "casings" and third, I have already installed a motor retainer, but what holds the motor in place during the propulsion stage?
[/QUOTE]

 

[Adam3836]

Here are some casing both cti and aerotech
It’s not to hard to build a motor for aerotech
Cti is slightly easier just buy the motor put it in the casing
Now single use doesn’t require these casing but for your L1 and high power your going to find yourself using these casing

 

[racerRobert]

LOVE LOVE LOVE the Zephyr - Got my L1 on H125 and L2 on a J290

 

[mtnmanak]

I am in the final stages of preparing for my L1 flight with a Zephyr, but I am confused about engines and whether or not they need casings. I am planning on using an H100 motor. First, is it powerful enough? Second, can you please explain "casings" and third, I have already installed a motor retainer, but what holds the motor in place during the propulsion stage?

All those questions and more:

https://www.mountainmanrockets.com/index.php/hpr-primer/

 

[Spitfire222]

I am in the final stages of preparing for my L1 flight with a Zephyr, but I am confused about engines and whether or not they need casings. I am planning on using an H100 motor. First, is it powerful enough? Second, can you please explain "casings" and third, I have already installed a motor retainer, but what holds the motor in place during the propulsion stage?

First, welcome to the forums.
Second, I guess I'll go ahead and be the jerk to say that you really should know the answers to those questions before attempting L1, especially if your motor selection is acceptable. The L1 certification should be a culmination of applying what you've learned, not something you aim for as the first thing you do in the hobby.

Fwiw, I'm in a similar position, currently building a Zephyr for my L1. The difference is I know the answers to those questions due to experience flying lots of LPR and MPR (low-power rocketry, and mid-power rocketry, respectively).

Others have already answered, so best of luck.

 

[JimH]

I got my L1 on a Zephyr with a H110. I bought a 3 grain CTI casing using one spacer. I chose the CTI hardware route instead of Aerotech to keep it as simple (read, idiot proof) as possible. I used Open Rocket software to do my calculations and checked my CG & CP and found out I had used FAR too much rocketpoxy to secure the through the wall fins which resulted in my CG being pulled too close to my CP. I had already purchased the 18" dual deploy extension for future use so I added that to my "stack" which extended my CG far enough to ensure a safe flight. I went single deploy with an 8 second delay and it was a text book flight of 1300' feet.