SparoAir air launched sounding rocket

[bobby_hamill]

Ok this will be my second ever posting of a scratch build.

The Sparoair 2 was a navy project to launch a sounding rocket from an aircraft

Here is a photo of the Sparoair 2 rocket that got me hooked

 

[bobby_hamill]

I was disappointed when I could not find more photos of the Sparoair 2 like the one above.
Then I stumbled across the grainy B/W image posted below

 

[bobby_hamill]

Fortunately I did some more searching and found a better copy of the same image but it had the tip of the nose cropped off

 

[bobby_hamill]

So here are the 2 photos I have to work with

 

[bobby_hamill]

Later I found information about the Sparrow 1 air to air missile that had data about the booster section that was used on the Sparoair 2 sounding rocket

 

[Nytrunner]

I've seen those exact photos on a previous thread here....I can't remember it though

 

[bobby_hamill]

the booster section is what I needed information about
NACA = National Advisory Committee of Aeronautics is the forerunner of NASA

 

[bobby_hamill]

Nytrunner,

I posted them on the watering hole to let the guys know what I was getting into

 

[bobby_hamill]

just realized I did a big boo boo and will half to start all my measurements over !!!!

The NACA paper I got the above 2 drawings from shows a diameter of 9 inches
The reason the 9 inch diameter was the test models were models not the real vehicle itself !!
It seams the test model was not a 1-1 scale but a 1.125 scale
So if I take all of the measurements in the drawing and multiply them by 88.801 percent I will
get the correct measurements

 

[aerostadt]

Good Luck. Are you building a scale model?

 

[bobby_hamill]

Sport scale

 

[bobby_hamill]

Also I wish to thank aerostadt for the 2 PDF files he downloaded for me and are attached below

 

[mbeels]

Looks like an interesting project. Is it two stage, or one stage?

 

[bobby_hamill]

1 stage simulated 2 stage maybe down the road could make a larger model and have it 2 stage

 

[bobby_hamill]

Sparoair 2

Length = 3.86 meters or 151.9685 inches
Diameter = .203 meters or 7.9921 inches

 

[bobby_hamill]

7.9921 inches is what percent of 9.0 inches ? = 88.8011 percent
Change 88.8011 percent to decimal = 0.8880
Multiply all 1.125 scale model measurements by 0.8880 will give measurements for the prototype rocket ( Sparrow ! Air to Air Missile )



results below

 

[bobby_hamill]

To get measurements for the BT-60 airframe divide 1.64 by 7.992 = 0.205
Multiply actual rocket measurements by 0.205 to get BT-60 airframe measurements

Results below

 

[kuririn]

With those big mid fins it might be prone to windcocking on anything less than a calm day.

 

[bobby_hamill]

I will be just using the booster section not the 2nd stage
The Sparoair 1 and Sparoair 2 used the same booster that was used on the Sparrow 1 Air To Air Missile

 

[mbeels]

With those big mid fins it might be prone to windcocking on anything less than a calm day.

I would expect that the effect of the mid fins would be to reduce weathercocking, rather than exacerbate it.

 

[Bruiser]

The drawings do not look like the rocket hanging on the aircraft. The rocket on the aircraft looks longer and the mid fins are shaped different. It looked familiar to me and I finally saw why when I was at the JonRocket sight.

It's a Skyflash that also used Sparrow motors. I doubt it's the rocket in that picture though because it was developed by the British for use on thier F-4 Phantoms...



-Bob

 

[kuririn]

The rocket in Bobby's pictures is a Sparoair. The Skyflash was a British air to air missile that used a Sparrow airframe and their own (superior) avionics. The clipped midfins is a later Sparrow variant that was used in the Skyflash, I believe. I was looking for a bigger Sparrow than the Estes version and found the Rocketarium Skyflash which would look identical to a Sparrow with the proper livery.


Estes Sparrow clone on the left, Rocketarium Skyflash on the right.

 

[Ez2cDave]

BOBBY,

Another VERY COOL missile is the AAM-N-4 Oriole

Dave F.

 

[bobby_hamill]

The drawings I posted is for a Sparrow 1 air to air missile that has a conical nosecone . And the Sparoair 2 uses the same booster as on the Sparrow 1 air to air missile. The Sparoair 2 has an ogive nosecone . And as Kuririn noted the 2nd stage fins on the Sparoair 2 was enlarged by 1/3 and had clipped fins

Also please note my build is for the Navy's air launched Sparoair 2 Sounding Rocket .

There is also a Navy air to air missile called the Sparrow.
The Navy used the Sparrow rocket motors on the Sparoair 1, 2 and 3 versions

I am posting data as how I obtained the measurements for the Sparoair 2 so bare with me
and it will all come together soon

 

[bobby_hamill]

Dave
The 2nd stage fins look like the diamond airfoil shape on the Nike.
Cool pic thanks for sharing

 

[Ez2cDave]

Dave
The 2nd stage fins look like the diamond airfoil shape on the Nike.
Cool pic thanks fore sharing

Bobby,

You are very welcome, sir !

Dave F.

 

[bobby_hamill]

Everything I have circled in red on the photo below is what I have confirmed measurements for.
As this build progresses I will show everyone how I came up with the unknown measurements

 

[Ez2cDave]

Bobby

Are these images helpful to you for the Booster ?

https://www.primeportal.net/hangar/weichao_chen/aam-n-3/

Dave F.

 

[bobby_hamill]

Sparrow = air to air missile
Sparoair = air launched sounding rocket


The motors available for the Sparoair were over age and declared unsafe
for launching directly from an aircraft. Therefore the sparoair used an ejection
Launch technique.

This is when the rocket is dropped from the aircraft and motor ignites by an internal timer inside the rocket itself

The sparoair 1 was 2 stage with a diameter of .203 meters and a overall length of 3.68 Meters

The stage connection was a folding diaphragm separation system

A sparrow 1 boat tail and fin assembly was used for the booster on Sparoair versions 1,2 and 3


A slot antenna in one of the 2nd stage fins was used for telemetry

The payload section was made up of a .140 meter cylinder and a .92 meter ogive
Nosecone

There were 2 external tunnels on the airframe to route antenna cable and the second stage firing lead

At launch the aircraft was at a 85 to 90 degrees and the rocket coasted for 5 seconds

After the booster burnout the rocket coasted for 17 seconds before second stage ignition.

92 kilometers was the nominal altitude reached


This was all for the Sparoair 1 vehicle

 

[bobby_hamill]

Dave
I already have those photos ( thanks for posting ) The drawings above show the measurements for the booster. Note those external channels / tunnels on the outside of the 2nd stage ? They were removed on the Sparoair 2 Sounding Rocket

BUT the external channels / tunnels on the outside of the 2nd stage were present on the Sparoair 1 Sounding Rocket