C-310/U-3 Centex Wing
San Marcos, TX
The U-3A began life as the Cessna model 310A (which had gained fame as the “Songbird” flown by Skyler “Sky” King of radio and TV fame) in January of 1953. The Cessna 310 gained wide acceptance for its good looks and excellent performance, so the USAF decided it would make an excellent replacement for its fleet of aging Beech C-45s in the administrative support, liaison and light cargo duties. Built as a four or five passenger fast executive transport, 546 U-3As were accepted by the United States Air Force. Originally designed as L-27As, the U-3A served as an executive transport, liaison aircraft and performed as chase planes in a number of units that operated the U-2. The average fly-away cost for these off-the-shelf commercial aircraft was $56,000. In 1962, when the Department of Defense implemented the Tri-Service Type Symbol System, the L?27A became the U?3A. The U?3A’s 2 six?cylinder Continental O?470?M engines produced 240 horsepower each and the USAF later retrofitted many A-models with all?weather gear.
The distinctive white-over-dark-blue paint scheme of USAF U-3s led to the unofficial, but widely recognized, nickname of “Blue Canoe.” Other services also operated U-3s, with the US Army acquiring 38 from USAF (25 As and 13 Bs) and the Navy acquiring 12 As (eight from USAF, four from the Army). Despite differing paint schemes on Army and Navy aircraft, the U?3 never lost its nickname of “Blue Canoe.”
Besides providing staff and administrative support with units around the world, the U-3 served as a test bed for new avionics equipment and conducted military navigational route surveys and certification checks of navigational aids. During the Vietnam War, USAF U?3s arrived in-country in May 1963 to support the Farm Gate aerial reconnaissance program by transporting film, photographs, and intelligence reports to combat units. The “Me-Too” During the late 1960s, the 100th Strategic Reconnaissance Wing at Davis-Monthan AFB in Tucson, Arizona, needed a chase plane and companion trainer for their Lockheed U?2 high?altitude reconnaissance aircraft (essentially a big, powered, single-seat glider). In the U-2, recognized as possibly the most difficult airplane to land properly and consistently, every pilot’s first flight was a solo flight.
The 100 SRW wanted an existing dual?control aircraft with control yokes (the U-2 sports a hefty control column/yoke) and chose the U?3A. According to Fred McNeill, a 100 SRW chase pilot for several years, they selected the straight-tail U?3A rather than the swept-tail U?3B because the B-model proved too unstable at the slow speeds needed for simulating U?2 approaches. The U?3A chase planes demonstrated turn rates, descent profiles, and traffic pattern airspeeds very similar to the U?2. In the U?2, pilots had to maintain airspeed during descent and landing within very tight tolerances to preclude aircraft and/or engine damage. And there were no U-2 simulators.
The U-2 and U-3 formation became a common sight over Tucson, and the pairing gained the nickname “U?2 and Me?Too.” The U?3 could intercept a descending U?2 at 15,000?18,000 feet at 160?180 KIAS, stay on its wing through the descent and traffic pattern, and slow to a typical U?2 threshold?crossing speed of 65 KIAS (10 KIAS above the U?3A’s stall speed and 18 KIAS below its minimum single?engine control speed). The chase U?3 always flew on the U?2’s right wing and discontinued chase ten feet above the runway — where a souped?up Ford El Camino would dash onto the runway and chase the U?2 to touchdown, calling out height above the runway and tail attitude (up, level or down) as the U-2 pilot worked to achieve the mandatory full stall landing.
With a pilot eye?to?ground height almost identical to the U?2, the U?3 allowed the chase/instructor pilots to train pre-solo U?2 pilots by managing the throttles to match the U?2 glide and “float” characteristics. Fred McNeill remembered that, as part of the training, the student had to learn to “level?off at one foot over the numbers and hold it there for the entire length of the 12,500?foot runway.” When the student could fly this profile consistently, the instructor landed the U?3 and stopped next to an already pre-flighted U?2, into which the student promptly hopped. For each student’s first solo, the U-2’s removable wingtip “pogo” landing gear (designed to support the wings on the ground and usually dropped at liftoff) remained attached to preclude inadvertent scraping of those long wings.
Meanwhile, the U?3 chase pilot climbed to 15,000 feet to wait for the fledgling U?2 driver. After join-up, the U?3 monitored the U?2 during several approach?to?stall exercises and the balancing of fuel between the wet wings (the older U?2 with its 103?foot wet span required manual fuel transfer for lateral trim before pattern entry). The U?3 pilot then calibrated his airspeed indicator against the U?2’s and proceeded to chase the U?2 through the traditional three traffic patterns and landings (breaking off the chase at ten feet and rejoining on takeoff leg). Successful completion of this “Dragon Lady Checkout” cleared the new U?2 pilot for solo training missions leading up to high altitude (above 70,000 feet) and long duration (12?16 hours) reconnaissance missions.
The 100 SRW maintained two U-3As and three qualified chase pilots at any time. Besides pre-solo U-2 training, the U-3s provided safety escorts for U-2 pilots returning from exhausting long?duration solo flights and regularly chased U-2s with in?flight emergencies.
Wing Span: 36? Length: 27’1 “ Height: 10’5? Maximum Speed: 257 M.P.H. Service Ceiling: 20,000 Ft. Range: 850 Miles Crew/Passengers: 2 crew, 3 passengers Armament: None Engines: 2 x 240 H.P. Continental 10-470-M engines Countries known to have operated the U-3 include Colombia, Ecuador, El Salvador, France, Indonesia, Iran, Madagascar, Mexico, Paraguay, Peru,Philippines, South Africa, Tanzania, Trinidad and Tobago, United States (US Air Force, US Navy, and US Army), Venezuela, Uruguay and Zaire.