61-7966 (SR-71A) Lost on the evening of 13 April 1967 after the aircraft entered a subsonic, high-speed stall. Pilot Captain Earle M. Boone and RSO Captain Richard E. (Butch) Sheffield ejected safely. The incident occurred 8 NM SE of Las Vegas, New Mexico (not Nevada). Sheffield estimates that #966 had less than 50 hours of flight time on her at the time of the crash.

1. On 13 April 1967, Major Earle M. Boone, FR53969, Pilot, and Major Vick, RSO, were schedules to fly SR-71A,
serial number 61-7959, on a Combat Crew Training Mission. Take-off was scheduled for 1035 Pacific Standard
Time. On the day preceding [sic] the flight Major Richard E. Sheffield, FV3039867, was selected to replace Major Vick, who was suffering from a cold and unable to fly. Major Boone and Major Sheffield attended the general briefing 12 April 1967. After briefing, the scheduled take-off time and aircraft were changed due to maintenance difficulties. This resulted in aircraft 61-7966 (ASPEN 29) being scheduled for a 1735 PST take-off. The original mission route and training accomplishments remained as briefed.


2. Flight planning was completed by the 9th Strategic Reconnaissance Wing Flight Planning Section. Crew briefing
was in accordance with existing policies and was conducted by the 1st Strategic Reconnaissance Squadron mission
briefing officer. The aircraft was preflighted by qualified maintenance crews, using established procedures, and no
discrepancies were apparent. Prior to flight, the flight crew filed their flight clearance and reported to the
Physiological Support Division building at the scheduled time. The pre-flight physical examination, pre-flight meal and suit-up operations were completed without discrepancy. The crew was driven to the aircraft and the hook-up
completed, and checked, without deviation. Prior to start, Engine Start, Taxi and all pre-take-off checks were routine and take-off was on time. The take-off and initial climb appeared normal to the launch crew.


3. Climb, acceleration and the first Mach 2.80, high altitude cruise leg were uneventful. Both crew members
reported moderate Clear Air Turbulence between Flight Levels 530 and 570. The pilot noted the left Compressor
Inlet Pressure indicating 1 to 1.5 PSI below the desired value and the right Compressor Inlet Pressure indicating 2 to 3 PSI below the desired value during acceleration through Mach 2.30. At Mach 2.80 both CIP indications were
normal for the cruise condition. The descent from FL 700 and the Air Refueling rendezvous with CISCO 53 were
normal with initial contact established at 0237Z, 74 nautical miles short of the End Air Refueling point at FL260. The delay in initial air refueling contact resulted from failure of the Air to Air TACAN rendezvous equipment to function properly. Tanker/receiver DME contact could not be established, as a result tanker/receiver separation could not be accurately determined and a slower than normal closure rate resulted. Maximum onload was scheduled and completed with 65,000 pounds transferred during one continuous contact. Due to delay in initial contact, a left turn was required at the End Air Refueling Point, fuel transfer was completed on the air refueling reciprocal heading at 025130Z and approximately FL250. The Air Refueling was reported normal by both the tanker and receiver crew. Receiver fuel quantity indicated 82,300 pounds at disconnect. This amount is higher than normal for the SR-71 but consistent with past fuel indications in this aircraft. After completion of Air Refueling the receiver cleared the contact position downward and to the left. The tanker received ARTC clearance and cleared the refueling track by initiating a left turn and establishing a climb toward a cleared cruise altitude of FL370. Major Boone increased power to minimum AB and started a 200 degree right turn at approximately FL240. During this time, the aircraft accelerated from approximately Mach 0.82 to approximately Mach 0.90. During the turn the pitch autopilot was engaged in the attitude hold mode and the roll autopilot engaged and Auto Nav mode selected. Mach 0.90 was maintained during the turn and altitude varied as permitted by available thrust. Major Sheffield had difficulty contacting Albuquerque center for climb clearance. Radio contact was established and climb clearance received at 0254:30Z with ASPEN 29 apparently in a right turn and 10 NM southwest of Las Vegas, N.M. VORTAC. Immediately following this clearance ASPEN 29 squawked IFF/SIF IDENT and acknowledge climbing to above FL600. At 0256Z the Albuquerque Center Sector 14 controller heard an unidentified transmission: "OK, let's go." At 0257Z Albuquerque attempted voice contact with ASPEN 29 to no avail. At 0258Z the radar target, identified as ASPEN 29 disappeared from the sector radar scope approximately 10 NM southeast of Las Vegas, N.M. VORTAC. Total flight time from take-off until final impact was one hour twenty three minutes based upon data supplied by Albuquerque FAA Center. Both crew members ejected successfully.

Search and Rescue:
1. Search and rescue response was almost immediate. The tanker CISCO 53 orbited the area immediately upon notification and picked up RSO survival radio and strobe light. He set up a track over the RSO and acted as airborne relay to other aircraft. ADF fixes were successful on the tone mode. First ground parties in the area were local law enforcement agencies and civilian population. Area secured by local law enforcement at the request of military. A random search was instituted for crew until arrival of Kirtland rescue mission commander, who organized ground and air search. Rescue parties came within 1/2 mile of crew members but were hindered by terrain, fences, and darkness. CISCO 53 directed rescue H-43 to general area of RSO until URC-11 survival radio contact was made. RSO directed helicopter to pick up pilot. Rescue time from incident to pick up was 2+45 hours. Helicopter and ground parties continued search for pilot all night.

2. The helicopter came very close to pilot as he was walking toward wreck site. At one point helicopter passed over pilot standing on a road at telephone pole light. Pilot felt he was sighted in helicopter searchlight and expected pick-up. Helicopter never spotted pilot despite wear of silver coated garment and a white helmet. Pilot effected self rescue and walked into wreck site 9+15 hours after incident.