Level 3 attempt Bong 8/15/15 LOC EZI-1350M

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tstone

tstone

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Going for level 3 at the Bong 8/15/15.
LOC Magnum 3E with reconfigured fins so now its' a EZI-1350M.
Body tube is all glassed, fin to fin too. Aerotech DMS 1350M for power.
Weight 22 lbs wet, motor is almost 11 pounds. I have to do the CG & possibly
add nose weight.

I certified L1 & L2 on an EZI-65 so this build was something I always had in mind.

EZI 1350M.jpg
 
That's awesome; can't wait to see the flight!

5.5" ? She looks great!

I'd guess that with the long-ish 3" motor and the large EZI fins, you won't need much, if any, noseweight. But better to check than to guess:D.

Hmm, might have to bring out my EZI on Saturday...haven't flown it in several years.

-Eric-
 
Very nice- I'll be there to see it. What is your predicted altitude on it?
 
tstone said:
Going for level 3 at the Bong 8/15/15.
LOC Magnum 3E with reconfigured fins so now its' a EZI-1350M.
Body tube is all glassed, fin to fin too. Aerotech DMS 1350M for power.
Weight 22 lbs wet, motor is almost 11 pounds. I have to do the CG & possibly
add nose weight.

I certified L1 & L2 on an EZI-65 so this build was something I always had in mind.
Click to expand...

That is sweet! The EZI-65 is a favorite 3FNC style rocket. Your upscale or redo of the LOC Magnum has turned out real nice. Shouls be a spectacularly high flight... Need pics and video when you get back.
 
Yes it was a great flight. No matter how many reloads there are out there its still hard to beat a AT White Lighting reload tons of white smoke.
Very close recovery for a L-3 flight.
 
Thanks to all for you support. Flight was successful, Youtube link below.
[video=youtube;TAmeTFHj_Uw]https://www.youtube.com/watch?v=TAmeTFHj_Uw[/video]
Most surprising was the speed. Open rocket predicted around 1,200 FPS, Madcow sim had it around 1,000 FPS, Smartlaunch
had it simmed around 650 MPH. It went almost 1,000 MPH & peeled half the paint off the nose!
 
Open Rocket had it close at 9122 feet. It went just shy of 10,000 ft.
 
Thanks DJS see youtube video below, I will be posting a better one later as I have time.
 
Good luck with your project, we would love to see it on the forum.
 
tstone said:
Thanks to all for you support. Flight was successful, Youtube link below.
[video=youtube;TAmeTFHj_Uw]https://www.youtube.com/watch?v=TAmeTFHj_Uw[/video]
Most surprising was the speed. Open rocket predicted around 1,200 FPS, Madcow sim had it around 1,000 FPS, Smartlaunch
had it simmed around 650 MPH. It went almost 1,000 MPH & peeled half the paint off the nose!
Click to expand...

M1350 to 650mph, hah! Maybe we should revisit some of those algorithms. Mine may be go over 1000.
 
The altimeters were Perfectflite Stratologger CF's that recorded almost identical data.
I have complete confidence in this altimeter.
 
Very nice flight and that Motor sure was peppy. I'm gonna have to try one of those. Congratulations on your successful certification.:cheers:
 
It actually stripped all the fiberglass from the payload section. The paint just went with the fiberglass. The glasline layer on LOC tubing doesn't make a good bonding surface for fiberglass wrap.
 
tstone said:
The altimeters were Perfectflite Stratologger CF's that recorded almost identical data.
I have complete confidence in this altimeter.
Click to expand...
I don't believe it is possible for the M1350 to power a 22 pound 5.5" rocket to 1000 mph. I don't believe the Newtonian physics allows it.

The PerfectFlite altimeters are excellent for determining apogee and for reliable deployment. They are not good for accurately determining rocket velocity due to mach shock transients. Velocity is determined from the dP/dt which is converted to d Alt/dt which is converted to velocity. Your rocket broke mach and there are shock waves that move from the aft end of the rocket to the NC tip as the rocket accelerated through Mach 1. The excessive dP/dt due to the shock wave passage is being interpreted at a greater than actually d Alt/dt which is then converted to a greater than actual velocity.

The PF will a accurately determine apogee and time to apogee. If you adjust your cd in the sim to obtain the same apogee and time to apogee and print out the velocity versus time data from the sim and from the altimeter and plot them on same time and velocity scales in a spreadsheet you will see the difference.

If you plot the PF calculated altitude and velocity versus time data, you should see the mach 1 transients in the altitude plot and the peak velocity occurring at the same time.

Bob
 
Ok I know it is not talked about but am I getting close to being a member
of the Chicago Rocket Mafia? I have a unique set of skills.
 
First rule about "Chicago Rocket Mafia"

....you don't ask to join. You get "told" you're "in" :wink:
 
bobkrech said:
I don't believe it is possible for the M1350 to power a 22 pound 5.5" rocket to 1000 mph. I don't believe the Newtonian physics allows it.

The PerfectFlite altimeters are excellent for determining apogee and for reliable deployment. They are not good for accurately determining rocket velocity due to mach shock transients. Velocity is determined from the dP/dt which is converted to d Alt/dt which is converted to velocity. Your rocket broke mach and there are shock waves that move from the aft end of the rocket to the NC tip as the rocket accelerated through Mach 1. The excessive dP/dt due to the shock wave passage is being interpreted at a greater than actually d Alt/dt which is then converted to a greater than actual velocity.

The PF will a accurately determine apogee and time to apogee. If you adjust your cd in the sim to obtain the same apogee and time to apogee and print out the velocity versus time data from the sim and from the altimeter and plot them on same time and velocity scales in a spreadsheet you will see the difference.

If you plot the PF calculated altitude and velocity versus time data, you should see the mach 1 transients in the altitude plot and the peak velocity occurring at the same time.

Bob
Click to expand...

Thanks Bob. I am not an altimeter expert & would like to see this issue debated by experts on the subject.
All I know is that I have used Perfectflite altimeters for many years & found them to be rugged, and reliable.
 
GRIFFIN said:
First rule about "Chicago Rocket Mafia"

....you don't ask to join. You get "told" you're "in" :wink:
Click to expand...

Ok well until then I'll just keep on burnin' AP & waiting for the call. Thanks for your help at Bong.
 
GRIFFIN said:
It actually stripped all the fiberglass from the payload section. The paint just went with the fiberglass. The glasline layer on LOC tubing doesn't make a good bonding surface for fiberglass wrap.
Click to expand...

That is for sure. You need to peel the glassine layer off before doing the lay up
 
tstone said:
Thanks Bob. I am not an altimeter expert & would like to see this issue debated by experts on the subject.
All I know is that I have used Perfectflite altimeters for many years & found them to be rugged, and reliable.
Click to expand...

Bob was not knocking Perfectflite. What he is describing is the issue with all barometric only altimeters and trying to determine velocity from them.
 

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