Update May 6th

The rudders , wings and fins have been given an additional sanding which has included a couple of layers of sanding sealer. Some aberrations have been filled with aircraft filler and sanded back. The through the wall fin tabs have been sanded to ensure conformity with the motor mount.

Additional Update 27th April 2017

Things have moved on quite swiftly in the last few weeks. The wings have been given an aerofoil cross section as have the rear fins. After a huge amount of sanding , both the upper and lower rudders now have a wedge shape and will be given a bit more TLC. They may receive a layer of thin ply to enhance the laminar flow at high speed.

The plan is to construct the chines initially on a 4” mail tube and then transfer them once the rudders , fins and wings have been stuck to the motor tube. The motor tube and the body tube have all been marked out to ensure correct alignment.  Once this has been done I’ll slip the BT over and then attach the chines!

The chines will be glassed to give them more rigidity.

This is the plan !

Update April 2017

It's been 2 years since my last update. I have spent some time trying to make the chines for the X15. This proved harder than I thought. As luck would have it Paul Clark has produced some rather amazing vacuum formed versions. These will make the task a lot easier.

I'm currently working on the upper and lower rudders.

THE NORTH AMERICAN X15

PROJECT X-15

The Thinking behind the project

For a number of years I've been fascinated with the North American X-15. The  X-15 was a rocket-powered aircraft operated by the United States Air Force and the National Aeronautics and Space Administration as part of the X-plane series of experimental aircraft.

The X-15  

The X-15 set speed and altitude records in the 1960s, reaching the edge of outer space and returning with valuable data used in aircraft and spacecraft design. As of 2014, the X-15 holds the official world record for the highest speed ever reached by a manned, powered aircraft. Its maximum speed was 4,520 miles per hour (7,274 km/h).

During the X-15 program, 13 different flights by eight pilots met the USAF spaceflight criterion by exceeding the altitude of 50 miles (80 km) thus qualifying the pilots for astronaut status. The USAF pilots qualified for USAF astronaut wings immediately, while the civilian pilots were awarded NASA astronaut wings in 2005, 35 years after the last X-15 flight. The sole USN pilot in the X-15 program never took the aircraft above the requisite 50 mile altitude.

Of all the X-15 missions, two flights (by the same pilot) qualified as space flights per the international (Fédération Aéronautique Internationale) definition of a spaceflight by exceeding 100 kilometers (62.1 mi) in altitude.

For more visual images this NASA produced documentary from 1962 is quite enlightening including the "technology. " 

https://www.youtube.com/watch?v=8pU3jdTwP4Q

The Planning 

Before building this craft I went through a number of ideas for it's construction. Initially I was going to build it with a 3" inch diameter rocket from scratch. I've built numerous scale rockets including a Quest X-15 and the 3" version was going to be an upscale version of that. After ploughing through books and data I received resources from the legendary Colin Rowe. He was one of the Rocketmen who built the Reliant Shuttle , rocket powered Mini and the Blue Peter rocket. 

And just in case you are unaware of these events! 

Reliant Robin space shuttle - Top Gear - Series 9 - BBC

https://www.youtube.com/watch?v=_b4WzWFKQ20

The Rocket Men: Blue Peter Rocket

https://www.youtube.com/watch?v=3kntaSdgfAw

After a chat with the rocketeering fraternity including Phil Charlesworth , Mike Brent and Chris Eilbeck I decided to build it with a 4 inch diameter! This proved to a wise move since there was a Rocksim CAD plan for a 4 " X15! The next hurdle was how faithful to the real thing was I going to be? The X15 has a strake which in the real thing contained flight controls and other forms of flight control. This can be seen in the picture below. It starts parallel to the rear of the canopy and extends right to the back of the craft. In the Rocksim file this was merely a piece of quarter inch plywood cut to the shape of the strake. However for this build I will be trying to be as faithful to the real thing as possible.

Cross section of North American X15 showing strake section of the fuselage. 

Cut away of X-15A-2 with  an additional pair of auxiliary fuel tanks attached beneath its fuselage and wings, and a complete heat-resistant ablative coating

 The rocket will be built with a 54mm motor mount with a PML Kwick-Switch for the option of 54mm/38mm and 29mm. Although launching this on a 29mm is very unlikely based on it's weight and fin area. It will also feature a PML 4" boat tail to be honest to the real thing. 

To ensure strength in flight and in recovery it will be fully glassed and the root areas will be reinforced with carbon fibre tape.

It will use a conventional ejection system for recovery deployment and a tracker for recovery on the ground. 

                                             Rocksim CAD file for X15 

I will be adding to this blog as the build progresses. 

3rd May 2014 

Update 

The parts have arrived from Rockets and Things in addition to those acquired from Mike Brent. I have now printed out the CAD formed fin guides. I cut these out using a scalpel, metal rule and a cutting mat. The pieces were 2 pieces of paper so these were joined together and then stick on a larger piece of paper. Once this was dry I then cut the piece out using the same tools and stuck these to light quarter inch plywood. 

Bottom Rudder and Top Rudder 

Left to right : Wing 1 , Wing 2  and Tail 1

After allowing these to dry I cut them out.

Nose Cone , Body Tube and Wings and Fins. Rudders below. 

The next stage is to cut the slots out for the wings, fins and rudder. I am also going to build the strake as per the plans but use this as a guide as to the shape of the real 3D strake.

January 2015 Update

After a number of months focusing on triathlon I'm now having a few weeks spending some time on this project. What initially started as build that would be purely a moderate homage has grown into something more complicated and detailed.
Since the last post I have been in contact with Paul Clarke who is an expert model builder and an expert on the X15. In addition to the vast amount of information from Colin Rowe the build is now substantial . Paul has made vacuum moulded parts including a canopy , chine ends , skid covers and other detailed parts. He has also helped me with the construction of the chines themselves. Quite simply a simple solution to a complex challenge. The chines are made of paper , then laminated , scored appropriately and then fibre -glassed. After communicating with Paul he refers to the strakes as chines. Since he is the absolute expert on the X15 I will now refer to these as chines!
The upper and lower rudders are now going to be modelled on the the real thing. So rather than just a cut piece of fibre glass reinforced ply they will now have depth! Parts have been cut and will be glued together and then sanded back to make the recognizable triangular cross section. The final layer will have a thinner piece of ply to make the sharper leading edge. 
In addition the recovery system parts have been selected as well as the boat tail and appropriate motor retention. Malcolm Jennings of Rockets and Things has made motor mounts to match the specific dimensions. 
It will now built with a 38mm motor mount ! 
All is needed is time to put it all together!