The perfect place for a perfect landing


Navy F-18s Take an Overhead Approach to Addison

October 20, 2014

f18 landOn their cross-country peregrinations, Addison Airport is a frequent stop for U.S. Navy F-18s. When the weather and traffic at the airport allow, they arrive in a fashion unlike that of civilian aircraft. The jet (or jets) enter the traffic pattern by flying directly over the runway, reverse their direction with a snappy 180-degree turn in a steep bank, followed by another 180-degree turn that puts them on final approach to the runway.

It may look like showboating, but it’s the safest, most efficient way to get a number of airplanes on the ground in the shortest amount of time and it minimizes the time the jet flies at slower speeds. That snappy turn is the break, and the steep bank angle increase the g forces on the airplane, which gobbles up its forward energy, or speed.

As described by the F-18 NATOPS (aircraft operating flight) manual, at the break the pilot reduces thrust and deploys the speed brake as needed during the downwind turn. “As the airspeed decreases through 250 knots, lower the landing gear and place the FLAP switch to FULL and ensure that speed brake is retracted.”

From their first day of training, naval aviators are taught to control airspeed by angle of attack (AOA), which is controlled by pitching the nose up or down. Power determines altitude; with a set airspeed (AOA), adding power results in a climb and reducing it establishes a descent. If the jet sinks below the desired final approach glide path, the aviator corrects this by adding power, which is why the engines’ volume sometimes changes on final approach.

An AOA indicator in the aviator’s field of view coincides with the desired on-speed for landing. NATOPS says: “On-speed without external stores and 2,000 pounds of internal fuel is about 125 knots [144 mph].  Add about 2.5 knots for each 1,000 pounds increase in fuel and stores.” Final approach concludes with “a firm touchdown at least 500 feet past the runway threshold.”

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CFM CV-2B Caribou is Vietnam Combat Veteran

October 5, 2014

CCV-2 sideOf all the aircraft that flew at Kaboom Town 2014, the largest was a veteran of the Vietnam War, the CV-2B Caribou, which is part of the Cavanaugh Flight Museum’s collection of airworthy aircraft. De Havilland Canada designed the Caribou to meet the U.S. Army requirement for a tactical transport capable of supporting troops in forward battle with supplies and by evacuating casualties. The prototype DHC-4 Caribou made its first flight in 1958. Caribou production ended in 1973 after De Havilland Canada built 307 aircraft.

Impressed with the DHC-4′s short takeoff and landing (STOL) capabilities, essential for operating in forward areas, the US Army ordered five for evaluation. The airplane could haul more than three tons, which works out to 26 fully equipped paratroops or 20 litter patients or two Jeeps. The rear ramp allowed quick loading and unloading and air drops of cargo delivered by parachute.

Initially designated the YAC-1 (with Y identifying it as an evaluator), in 1962 the Army changed it to CV-2 and named it the Caribou. It purchased 159 aircraft for use in Vietnam, where larger cargo aircraft such as the C-123 Provider and the C-130 Hercules could not land on the shorter landing strips. In 1967, when the U.S. Air Force was given responsibility for all fixed-wing tactical transports, the Caribou was redesignated the C-7 upon this interservice transfer.

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