F-111B numbers 1 to 3 were initial prototypes; and No.
4 and 5 were prototypes with lightened airframes.
No.
6 and 7 had lightened airframes and improved TF30-P-12 engines and were built to near production standard.
These were also approximately 2 feet (0.6 metres) longer due to an added section between the cockpit and radome.
The first five aircraft included Triple Plow I intakes.
The last two had Triple Plow II intakes.
The first three B-models were fitted with ejection seats and the remainder included the escape crew capsule.
F-111B numbers 1 to 3 were initial prototypes; and No. 4 and 5 were prototypes with lightened airframes. No. 6 and 7 had lightened airframes and improved TF30-P-12 engines and were built to near production standard. These were also approximately 2 feet (0.6 metres) longer due to an added section between the cockpit and radome. The first five aircraft included Triple Plow I intakes. The last two had Triple Plow II intakes. The first three B-models were fitted with ejection seats and the remainder included the escape crew capsule.
General Dynamics–Grumman F-111B