Boeing B747 AANBNCP (Advanced Airborne National Command Post)

[Orionblamblam]

Here's a surprising drawing... the 747 AANBNCP (Advanced Airborne National Command Post), later the E-4 in a remarkable level of detail. It does, however, differ in a lot of ways from the final product. Note the two extra engines, making this a design for a six-engined bird.

And no, it's nowhere marked "classified" or "secret" or any such.

 

[starviking]

Here's a surprising drawing... the 747 AANBNCP (Advanced Airborne National Command Post), later the E-4 in a remarkable level of detail. It does, however, differ in a lot of ways from the final product. Note the two extra engines, making this a design for a six-engined bird.

Six-engines for increased weight? Or were they trying to decrease the load on the individual engines?

 

[Orionblamblam]

Here's a surprising drawing... the 747 AANBNCP (Advanced Airborne National Command Post), later the E-4 in a remarkable level of detail. It does, however, differ in a lot of ways from the final product. Note the two extra engines, making this a design for a six-engined bird.

Six-engines for increased weight?

The two additional engines are dinky in comparison to the standard turbofans, and are described as "LTV Power Pods." They have straight exhaust ducts, but were clearly meant to be some sort of power generators. Unless "Power Pod" means some sort of takeoff assist, though that seems to me unlikely given how small they are.

 

[aim9xray]

The two additional engines are dinky in comparison to the standard turbofans, and are described as "LTV Power Pods." They have straight exhaust ducts, but were clearly meant to be some sort of power generators. Unless "Power Pod" means some sort of takeoff assist, though that seems to me unlikely given how small they are.

That's your answer then. The same approach was used on the one and only RC-135E "Lisa Ann" / "Rivet Amber" - except on that jet, the portside pod had the APU and the other was the heat exchanger for the 7.5 megawatt side-looking phased array radar. The APU was a Lycoming T55-L-5 driving a 350 kva generator. LTV / E-Systems did the mods to the former C-135B - that correlates to your drawing nomenclature.

 

[starviking]

The two additional engines are dinky in comparison to the standard turbofans, and are described as "LTV Power Pods." They have straight exhaust ducts, but were clearly meant to be some sort of power generators. Unless "Power Pod" means some sort of takeoff assist, though that seems to me unlikely given how small they are.

Cheers for that Scott.

 

[Matej]

This should be real general internal arrangement of the E-4 and VC-25A. Found in public sources.

 

[Triton]

That is a box of awesome! ;D Thank you for sharing!