Boeing painted the BV-107/II-2 prototype N6679D (c/n 10) in USAF titles for suitability trials with USAF Texas Towers. (See photo above) During Dec 1962, Boeing also sent a pre-delivery New York Airways BV-107/II-2 (N667?D) to Otis AFB for suitability trials. In early 1962, the US Air Force ordered twelve XH-49A (based on the BV-107/II-1) for Texas Tower support and Artic Search And Rescue (SAR) duties. The airframes were assigned USAF serials 62-12473/12484. In October 1962, the designation was changed to CH-46B. In late 1962, the USAF visited the Vertol factory in Morton, PA and determined that Vertol could not meet the rigid delivery requirements, and so cancelled the contract with no airframes having entered produciton. The USAF requested and the USN transferred three SH-3As directly to the USAF and the USAF ordered another three Sikorsky CH-3Bs (S-61As) for delivery in early 1963. The USAF asked Sikorsky to develop the S-61R (CH-3C).