Boeing YC-14
Pima Air and Space Museum
Aug 6, 2004
The YC-14 was one of the competitors for the USAF program to replace the Lockheed C-130 Hercules. Called AMST for Advanced Medium STOL (Short TakeOff and Landing) Transport, its competitor was the McDonnell Douglas YC-15. It was designed to hold an Army M-60 tank, and still fly in and out of short strips. It could takeoff in 1000ft., with a payload of 27,000lbs.
The aircraft low speed capabilities relied on Upper Surface Blowing, or USB. The large GE CF-6 engines would blow its exhaust over the oversized flaps, generating increased lift.
The USAF ended the program in 1979, when the requirements changed. For instance, neither aircraft design could carry the newer M-1 main Battle Tank. The requirement for a larger transport also meant larger airfields. So, both designs were enlarged, with Boeing designing a 3 engine version of the YC-14. A NASA engineer involved with the program once told me that their was concern, that if either wing mounted engine failed on takeoff or landing, the differential lift could result in the loss of the aircraft. For whatever reason, McDonnel Douglas was declared the winner with their C-17.
Here you can see the large flap actuators that would both extend and drop the large flaps.
Boeing YC-14
Pima Air and Space Museum
Aug 6, 2004
The YC-14 was one of the competitors for the USAF program to replace the Lockheed C-130 Hercules. Called AMST for Advanced Medium STOL (Short TakeOff and Landing) Transport, its competitor was the McDonnell Douglas YC-15. It was designed to hold an Army M-60 tank, and still fly in and out of short strips. It could takeoff in 1000ft., with a payload of 27,000lbs.
The aircraft low speed capabilities relied on Upper Surface Blowing, or USB. The large GE CF-6 engines would blow its exhaust over the oversized flaps, generating increased lift.
The USAF ended the program in 1979, when the requirements changed. For instance, neither aircraft design could carry the newer M-1 main Battle Tank. The requirement for a larger transport also meant larger airfields. So, both designs were enlarged, with Boeing designing a 3 engine version of the YC-14. A NASA engineer involved with the program once told me that their was concern, that if either wing mounted engine failed on takeoff or landing, the differential lift could result in the loss of the aircraft. For whatever reason, McDonnel Douglas was declared the winner with their C-17.
Here you can see the large flap actuators that would both extend and drop the large flaps.