Rocket engine combustion chamber

1. An engine comprising:

a combustion chamber;

a smooth wall nozzle;

a plurality of tube assemblies for conveying a coolant;

each of said tube assemblies having an internal ferrule with a free end;

a transition zone between said combustion chamber and said smooth wall nozzle;

said transition zone having a coolant system which includes a first manifold abutting said nozzle and being formed from a non-copper material through which a coolant flows and a second manifold abutting said first manifold;

said free end passing through said second manifold and terminating in said first manifold; and

said second manifold being formed from a material different from said non-copper material.

2. An engine according to claim 1 , wherein said combustion chamber has a regenerative cooled tubular chamber construction.

3. An engine according to claim 1 , wherein said first manifold is formed from steel.

4. An engine according to claim 1 , wherein said first manifold is formed from a nickel based material.

5. An engine according to claim 1 , further comprising said second manifold being formed from a copper based material.

6. An engine according to claim 1 , wherein said second manifold abuts said first manifold and is joined to said first manifold.

7. An engine according to claim 1 , further comprising said second manifold having a plurality of holes for receiving said free ends.

8. An engine according to claim 7 , wherein each said tube assembly has a round cross section and said second manifold has a smooth wall in line with the round cross section of each said tube assembly.

9. An engine according to claim 1 , wherein said second manifold is a leading edge manifold and said first manifold is an aft manifold.

10. An engine according to claim 1 , wherein said first manifold has a plurality of holes and said second manifold has a plurality of holes which aligns with said holes in said first manifold.