From Oct. 20 to Nov. 3, 1967 the A-12 and the SR-71 were pitted against each other in a recon fly off, code named “Nice Girl.”

The SR-71, unofficially known as the “Blackbird,” is a long-range, advanced, strategic reconnaissance aircraft. The first flight of an SR-71 took place on Dec. 22, 1964, and the first SR-71 to enter service was delivered to the 4200th (later 9th) Strategic Reconnaissance Wing at Beale Air Force Base (AFB), Calif., in January 1966. The US Air Force (USAF) retired its fleet of SR-71s on Jan. 26, 1990, because of a decreasing defense budget and high costs of operation.
Throughout its nearly 24-year career, the SR-71 remained the world’s fastest and highest-flying operational aircraft. From 80,000 feet, it could survey 100,000 square miles of Earth’s surface per hour.
The SR-71 was based on another Mach 3, high altitude reconnaissance aircraft, the A-12 Oxcart.
The A-12 was operated by CIA but its operational lifetime was short-lived because the CORONA reconnaissance satellite, which was first launched in June 1959, began providing worldwide imagery without much of the risk associated with airborne reconnaissance. At the same time, the SR-71 began operations with the US Air Force (USAF), leading to the A-12’s retirement in 1968.
Why was the SR-71 Blackbird chosen over the A-12 Oxcart?

From Oct. 20 to Nov. 3, 1967 the A-12 and the SR-71 were pitted against each other in a recon fly off, code named “Nice Girl” over the US that included refueling, flying identical routes 1 hour apart on three different days and both would complete the full sortie with collection sensors operational.
On the first attempt, the SR-71 was OK but the A-12 had a problem. On the 2nd day, the reverse was the case. On day 3, both aircraft successfully flew the route. On that day, it was under-cast for the northern part (from California to Kentucky) and the A-12 could only photograph clouds while the SR-71 was able to collect ELINT and SLR data. After air refueling, both accelerated and climbed over the Gulf of Mexico. From New Orleans to the San Francisco area, the weather was CAVU and both aircraft were able to provide their full collection capability/data for the evaluation.
The aircrews that took part in the program were:

- Lt. Col. Al Hichew and I, Maj. Tom Schmittou flew mission #1.
- Maj. John Storrie and Maj. Coz Mallozzi flew mission #2 Maj.
- Bill Campbell and Capt. Al Pennington flew mission #3.
- Jack Weeks flew all three A-12 missions.
The first two flight days were inconclusive. After the third day of flights, it was determined by Intelligence evaluators that the SR-71 was a better overall investment. A-12s had much better cameras – wider swath and higher resolution but the SR-71 collected more types of intelligence than the CIA aircraft could. These other sensors were infrared detectors, side looking airborne radar, and ELINT-collection devices needed for the SR-71 mission of post-nuclear-strike reconnaissance.
The conclusion was they picked the SR-71 to continue flying. The A-12s were retired. The A-12s were put in hangars until 1984.
Be sure to check out Linda Sheffield Miller (Col Richard (Butch) Sheffield’s daughter, Col. Sheffield was an SR-71 Reconnaissance Systems Officer) Facebook Page Born into the Wilde Blue Yonder for awesome Blackbird’s photos and stories.
Photo credit: Lockheed Martin and U.S. Air Force

I know it’s inaccurate, but I think of both as Blackbird’s. And I’d have thought that the 71 would have ended up with the best tech from both versions.
Besides the obvious stated differences, were there any other practical differences?