XV-15 litho - NASA's History Office

Incidents
Door Strike
On September 2, 1977, during the start of a ground run the test pilots noticed
that the door lock caution light was illuminated as the normal engine start procedure
was initiated. This caution light, which was connected to a sensitive
microswitch, indicated the position of the door bolt. This had previously been the
source of numerous nuisance indications which were suspected to be due to the
improper setting of the microswitch position. Because of this, the position of the
door handle was visually checked, found to appear to be in the correct position,
and the engine start procedure was continued.
After less than three minutes following engine start, with the proprotors in the
airplane mode and while increasing power, the cabin door opened and was struck
by the proprotor blades, scattering pieces of aluminum over the aircraft.
The crew immediately began to convert back to the helicopter mode, shut down
the engines, and cut off the fuel supply. There were no injuries.
The incident which damaged the three right hand blades (one beyond repair) and
destroyed the cabin door, was a classic example of ignoring a troublesome caution
light that was, in fact, providing valid information.
Because the XV-15 airframes were essentially hand crafted, the door from
N703NA would not fit the N702NA fuselage satisfactorily, so a new door was
fabricated. Modifications to reduce the probability of a repeat of this incident
included a small window in the frame to allow visual inspection of positive
latching of the door bolt and the installation of a short cable inside the cabin for
the crew to connect to the door after entry.
In-Flight Engine Failures
After the initial XV-15 flight envelope expansion activities demonstrated the predicted
favorable handling qualities and performance capabilities, the Government
Project Office began to plan for the second phase of flight tests with the tilt rotor
aircraft in support of potential military applications. To better understand military
application requirements, and to inform key civil and military aviation planners
of the capabilities offered by tilt rotor aircraft, a Tilt Rotor Experiments
Planning Workshop was held on December 4 and 5, 1979, in Arlington, Texas.
The meeting was attended by about 100 senior military and civilian personnel
from each of the U.S. armed services. Presentations were made by Government
Project Office personnel, senior Government and Bell managers and test pilots.
During the second day of the meeting, the managers were informed that XV-15
aircraft N702NA, on approach to Arlington Municipal Airport, only a few miles
away from the meeting site, experienced an engine failure. It was reported that
the chase aircraft had observed smoke trailing from the right nacelle at about the
same time that the XV-15 flight crew heard a screeching noise, followed by the
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