So the TF39 was made by GE, and was the first high-bypass turbofan. Then there is the JT9D, made by P&W. These engines are both very similar, besides the N1 fan on the TF39. Was there some sort of alliance between the two manufacturers or something during the development of the two engines. It's the same with the TF33 and JT3D. So what's the story???

No alliance. The TF-39 and JT9D were competitors for the C-5.

 

The TF33 and JT3D are military and civilian designations of the same engine.

The TF33 and JT3D are military and civilian designations of the same engine.

 

Thanks for your response.

So with the TF33, why did GE take P&W's engine and change it? It's the same underlying engine, the JT3D. There must have been something between the two manufacturers, since they shared their engine.

Regards

FTF is a standard US military designation - Turbo Fan. All military turbofans are TFxx. The TF33 was built by P&W - TF39 by GE.

Ah, so that's where my confusion came from. I thought TF was another type of GE engine, like "CF" in CF6. Thanks for clearing this up for me

Regards