Question of the Month

Current Question

The following question has arisen as a result of the crash of Comair/Delta Flight 5191 in Lexington Kentucky in August. 

HOW DOES A PILOT KNOW IF HE IS ON THE CORRECT RUNWAY FOR TAKEOFF  AND NOT ON SOME OTHER RUNWAY?

ANSWER:

The FAA or other airport controller will have cleared the pilot for takeoff prior to his beginning the taxi to the active runway. This clearance provides the pilot with the runway number such as Runway 22 in Lexington. This runway number is also the departure heading of the runway, ie: 220 degrees. Beside physical runway markings painted directly on the runway and airport signs directing the pilot to taxi ways and runways, the pilot generally has at least 2 very important instruments in his cockpit that can confirm that he is on the correct runway. These two instruments are his Directional Gyro [DG] and his magnetic compass. Once the pilot has aligned his aircraft for takeoff along the axis of the departure runway, the DG and Magnetic Compass should display the same heading as the assigned runway number. That would mean that if the aircraft was to depart on runway 22 the DG and magnetic compass in the cockpit should indicate headings of approximately 220 degrees.  If the pilot is on the incorrect runway such as runway 26, as was the case in Lexington, the pilot upon checking his instruments should be made aware that he was not aligned in the proper direction [assigned heading of 220 degrees and actual heading of 260 degrees indicating that he is 40 degrees off of the proper takeoff alignment] and therefore not on the proper runway OR that his instruments are not reading properly. The pilot would in either case be aware of a significant problem BEFORE committing an attempted takeoff.

Note: This procedure would of course not be applicable if there were two parallel runways at the airport, but this situation would most likely only occur at larger airports which would likely have operational ground RADAR to allow for simultaneous takeoffs on the parallel runways and would also provide additional warnings to the pilot that he was on the incorrect departure runway. Blue Grass airport in Lexington Kentucky does not have parallel runways.