NTSB Factual Report

On July 8, 2001, at 1214 eastern daylight time, a Cessna 402C, N760EA, operated by Cape Air as flight 65, was destroyed when it struck the runway after takeoff from Logan International Airport (BOS), Boston, Massachusetts. The certificated airline transport pilot received minor injuries. Visual meteorological conditions prevailed for the positioning flight destined for Nantucket, Massachusetts. Flight 65 was operated on an instrument flight rules (IFR) flight plan under 14 CFR Part 91.

According to an inspector from the Federal Aviation Administration (FAA), the departure procedure at Boston was to listen to the ATIS, contact departure control for departure clearance, then monitor ground control and wait to be called. The pilot did this and at 1208, the pilot was contacted by the ground controller who said:

"cair sixty five, boston ground, taxi to runway two two right, intersection departure at fifteen right, via kilo, november, fifteen right, there will be a wake turbulence delay."

The pilot replied:

"fifteen right, we're going kilo, november, we'll ah, we'll go ahead and waive the non heavy, sixty five."

As the airplane neared the departure point, the ground controller instructed the pilot to monitor the control tower.

At 1212:45, US Airways flight 677, was cleared for takeoff on runway 22R. The flight crew acknowledged the clearance at 1212:50.

At 1213:23, the local controller transmitted:

"cair sixty five, boston, caution wake turbulence preceding full length departure was a seven thirty seven, traffic holding full length, turn right into position, runway two two right from one five left, cleared for takeoff." The pilot replied, "we're cleared to go from one five right, cair sixty five thanks.", after which the local controller repeated the takeoff clearance.

At 1214:11, an unknown person said, "what happened there", and at 1214:13, an unknown person said, "better roll the crash crew", to which the local controller replied, "we got it going."

A witness was taxiing north on taxiway KILO, approaching taxiway CHARLIE. He first observed the airplane just after it became airborne, and its landing gear was retracting. He said the airplane was in a shallow climb. He thought the airplane had reached an altitude of 30 feet when it entered a left turn with an "abrupt left roll." The angle of bank continued to increase, and as the airplane rolled past about 110 degrees, the left wing contacted the runway. The airplane continued to roll over on its back with the nose and vertical stabilizer striking the runway. The airplane then slid off the runway into the grass, pivoted on the left wing, then came to rest and caught on fire.

Emergency personnel responded to the accident site and extinguished the fire. The pilot, who was able to exit the airplane without assistance, was treated by emergency personnel at the site, and then taken to a local hospital.

The airplane that departed just prior to the accident was a Boeing 737-300, with a takeoff weight of 118,635 pounds. The pilot had used a 5-degree flap setting for takeoff, and he estimated that the airplane used about 5,000 feet of runway to become airborne.

The accident pilot reported that he thought the nosewheel from the preceding airplane was lifting off as the airplane passed by his position. He could see exhaust smoke, and noticed that both the airplane and the exhaust smoke had drifted to the left of the runway centerline at the time of his departure.

The pilot further stated that the airplane's ground roll was about 1,500 feet, and after liftoff, with a positive rate of climb, he initiated landing gear retraction. Passing through 50 to 100 feet above the runway, he felt a wobble, and the left wing dropped about 90 degrees. The airplane assumed a nose down attitude, struck the runway, and rolled inverted. The airplane slid into the grass area and stopped, then a fire developed. The pilot reported that he was able to exit through the cabin door.

When asked, the pilot reported that he had encountered wake turbulence and there were no problems with either the airplane or the engines.

The Director of Flight Operations for Cape Air reported that at Boston, when using runway 22R for departure, it was common to make an intersection departure from runway 15.

Runway 22 was 7,860 feet long. The centerline of runway 15 crossed runway 22 about 3,885 feet from runway 22's departure end.

According to the Aeronautical Information Manual (AIM), Section 4-3-10 Intersection Takeoffs:

"d. Controllers are required to separate small aircraft (12,500 pounds or less, maximum certificated takeoff weight) departing (same or opposite direction) from an intersection behind a large non-heavy aircraft on the same runway by ensuring that least a 3-minute interval exists between the time the preceding large aircraft has taken off and the succeeding small aircraft begins takeoff roll. To inform the pilot of the required 3-minute hold, the controller will state, 'Hold for wake turbulence.' If after considering wake turbulence hazards, the pilot feels that a lesser time interval is appropriate, the pilot may request a waiver to the 3-minute interval. To initiate such a request, simply say, 'Request waiver to 3-minute interval,' or a similar statement. Controllers may the issue a takeoff clearance if other traffic permits, since the pilot has accepted the responsibility for wake turbulence separation."

NTSB Probable Cause

The pilot's improper decision to waive the wake turbulence hold time, and his subsequent loss of control when wake vortex turbulence was encountered.