Air-Launched Weapons

USAF procures new and improved 'bunker buster' bombs

28 June 2018

An F-35A aircraft conducting a test release of a GBU-31 BLU-109 bomb during trials. The USAF has awarded its first contract for the successor BLU-137/B penetrator warhead. Source: Lockheed Martin

The US Air Force (USAF) has issued a contract for a new penetrator warhead to replace its current BLU-109/B and BLU-109C/B systems.

The award on 27 June will see Superior Forge and Steel Corporation deliver 300 (possibly rising to 3,500) of the improved BLU-137/B penetrator warheads. Valued at USD476.9 million, the indefinite-delivery/indefinite-quantity award will run through to 3 May 2020.

The USAF first declared its intention to procure an improved ‘bunker buster’ bomb with a draft request for proposals (RFP) that was issued in December 2016. The draft RFP actually covered the procurement of up to 15,000 of the 2,000 lb warheads running through to 2021.

No technical specifications for the BLU-137/B were given in either the draft RFP or the contract notification, except to say that it is intended to provide improvements in capability and survivability over the BLU-109/B and BLU-109C/B.

As with the incumbent BLU-109, the BLU-137/B will be used to defeat hardened targets, such as secure command-and-control bunkers and other protected facilities.

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