LAX97FA059

NTSB accident investigation · Morane-Saulnier MS760 II · Irvine, CA · November 30, 1996

Accident · FatalField investigationFinal report
Date
November 30, 1996, 13:07 local (21:07 UTC)
Place
Irvine, CA
Injuries
3 fatal
Damage
Destroyed
Phase of flight
Approach
Aircraft
N2TEMorane-Saulnier MS760 II
Weather
Visual (VMC) · Day
Status
Completed · report April 10, 1998
Report
Approved by Office Director
FAA report
19961130036869A
Case key
29594

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot's failure to maintain an adequate airspeed margin while maneuvering in a steep banked turn to the landing runway, which resulted in an inadvertent stall/spin. Factors in the accident were: the pilot's inadequate preflight inspection of the aircraft in that he departed with the boarding ladder attached to the aircraft's exterior; the pilot's inadequate in-flight planning in that he flew a traffic pattern so close to the runway that it required excessive bank angles to align the aircraft with the landing runway; and the aircraft's probable encounter with the periphery of a weakened B-757 wake turbulence, which increased the wing's angle of attack beyond the stall point at a critical point during a steep banked turn.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of control - in flightApproach - vfr pattern - base leg/base to final
Aircraft preflight - inadequatePilot in commandFactor
In-flight planning/decision - inadequatePilot in commandFactor
Maneuver - excessivePilot in commandCause
Airspeed(vs) - not maintainedPilot in commandCause
Wake turbulence - encounteredPilot in commandFactor
Stall/spin - inadvertentPilot in command
In flight collision with terrain/waterDescent - uncontrolled

Analysis

Shortly after takeoff, the pilot radioed the air traffic control tower declaring an emergency and stating his intent to return for landing. He stated that he had taken off with an external boarding ladder attached to the aircraft. Several witnesses reported that the aircraft's downwind leg was too close to the airport causing the aircraft to overshoot the turn to the final approach course, and that the pilot increased the aircraft's bank angle as he tried to align the aircraft with the landing runway. As the aircraft was intercepting the final approach course, it abruptly rolled inverted, the nose dropped, and the aircraft spiraled onto the roof of an industrial building. A Boeing 757 aircraft, landing on the same runway, had passed over the accident site 2 minutes and 17 seconds earlier. The B-757 was cleared to land before the accident aircraft received a takeoff clearance and was on the runway when the pilot declared the emergency and turned downwind. The local controller did not issue a wake turbulence advisory. Experienced MS760 pilots reported that the aircraft will exhibit no adverse performance or safety affects with the boarding ladder attached.

Factual narrative

History of flight

On November 30, 1996, at 1307 hours Pacific standard time, a Morane-Saulnier MS760 II, N2TE, rolled inverted and crashed into an industrial building from approximately 500 feet agl during an emergency landing approach at John Wayne Airport, Santa Ana, California. The aircraft was destroyed and the commercial pilot and two passengers were fatally injured. Visual meteorological conditions prevailed for the local area personal flight.

Shortly after takeoff from runway 19R, the pilot radioed the John Wayne Air Traffic Control Tower declaring an emergency and stating his intent to return for landing. He stated that he had taken off with an external boarding ladder attached to the aircraft. The controller cleared the aircraft to land on the same runway it had just departed; however, a Boeing 757 aircraft, on 2-mile final approach from the north when the accident aircraft departed, landed on the same runway in the interim.

There were several witnesses to the 4-minute flight. One reported observing the aircraft taxi out with the ladder on the right-hand side of the aircraft. Other witnesses reported that the aircraft's downwind leg was too close to the airport causing the aircraft to widely overshoot the turn to final approach, and that the pilot increased the bank angle as he tried to align the aircraft with the landing runway. Several non-pilot witnesses at various locations under the aircraft's flight path reported being attracted to the aircraft by its low altitude, slow speed, loud engine noise, and unusual proximity to the airport.

According to the witnesses, as the aircraft was intercepting the final approach in a 30- to 45-degree right bank about 1 mile from the landing threshold, the aircraft suddenly rolled to the right until it was inverted. It spiraled downward and completed approximately 1.5 turns before impacting the building. Two airline pilots who observed the accident stated that they saw no pitching or wing rocking before the roll commenced.

A witness located at the MacArthur Avenue Golf Course, approximately 1/4 mile west of the accident site, reported that his attention was attracted to the aircraft because jet aircraft do not usually make their traffic patterns so close in to the airport and so low. He reported that, while facing north, the aircraft approached from his left rear and flew over his position about 300 feet agl. The aircraft banked to the right until the wings were in a near vertical bank angle and then the aircraft "corkscrewed" to the ground. The engine thrust sound was "normal" when it flew over him, then became a "high pitch whine" and became silent during the spin.

The flight on which the accident occurred was the pilot's third flight of the day in the accident aircraft. Another pilot flew in the left seat of the aircraft on the first flight of the day and was receiving instruction from the accident pilot who sat in the right seat. He stated that there were no mechanical irregularities with the aircraft and reported that the pilot made no comment to him about any discrepancies with the aircraft. This flight was an aerial photo mission to photograph the aircraft for an upcoming magazine article. The left seated pilot held a private certificate with type ratings in two jet aircraft types but was not type rated in the accident aircraft..

Prior to the third (accident) flight the aircraft was refueled with 174 gallons of Jet A fuel. According to the refueler, 60 gallons was pumped into each tip tank and the remainder was added to the fuselage tank, which brought it to about 2/3 full.

Witnesses stated that when the aircraft taxied for departure, the pilot was in the right front seat and a passenger, who was writing a magazine article on the aircraft, was in the left front seat.

Personnel information

The pilot was a USAF Master Sergeant stationed at Vandenburg AFB, California. He was an administrative aide in the 30th Communications Squadron. He learned to fly as a civilian in 1987, and was active as a flight instructor in the Vandenburg Aero Club. Between 1992 and October, 1994, he was the Chief Flight Instructor for the club. In 1994, when the club became an FAA Approved Part 141 school, a full-time chief flight instructor was hired and the pilot became the Assistant Chief Flight Instructor, a position he held at the time of the accident.

The pilot owned his own MS760 aircraft. A pilot who had flown with him in that aircraft reported that his aircraft's flight controls were a conventional control wheel arrangement as opposed to the accident aircraft, which had a control stick. This pilot also reported that it was the accident pilot's usual practice to fly landing approaches by reference to the "diamond speed" on the angle of attack indicator, and that the angle of attack indicator was virtually impossible to see from the right seat. When the accident pilot flew his aircraft from the right seat, it was his practice to have the pilot in the left seat call out his approach angle of attack relative to the "diamond."

The pilot's activities in the last 72 hours was compiled by the Safety Adviser to the Vandenburg Aero Club and is attached.

According to the pilot's logbook, in the 90 day period before the accident, he had given dual instruction in the accident aircraft on 6 flights totaling 7.8 hours, 18 landings, and 7 instrument approaches; exclusive of the two prior flights on the day of the accident.

The passenger in the left front seat held a private pilot certificate with an airplane single engine land rating. The passenger had no known experience in jet aircraft and had accrued a total flight time of 220 hours.

Aircraft information

The MS760 aircraft has a canopy over the passenger compartment, which is normally opened and closed (for boarding) by an electric motor; however, there is also a manual crank located on the right-hand cabin side wall by the right front passenger's right knee. There is an interlock microswitch on the boarding ladder receptacle which prevents the canopy from being electrically closed when the ladder is on the aircraft. However, the manual crank can open or close the canopy regardless of whether or not the ladder is attached. There is no cockpit annunciation of the ladder being attached to the exterior, nor is the ladder visible from the cockpit with the canopy closed. According to a pilot familiar with the aircraft type, it is not uncommon for the electrical canopy system to malfunction due to sensitive rigging of the interlock microswitch, and many pilots routinely crank the canopy closed rather than use the electric system. The pilot who flew aboard the aircraft on the first flight of the day thought he recalled that the pilot had closed the canopy using the manual crank.

It was noted in examining the wreckage that one of the two wires attached to the interlock microswitch at the right-hand ladder attachment point had a loose wire at the crimp of the ring terminal. Another MS760 aircraft was examined and the same wire was purposely disconnected from the canopy interlock microswitch to duplicate this condition. With the wire disconnected from the microswitch, the otherwise operational canopy would not close electrically. It was noted, however, that the inhibiting function of the microswitch was sensitive to placement of the ladder in the fuselage receptacle and to the rigging of the switch mechanism.

The flight instructor who trained the pilot for his type rating in the aircraft has about 1,000 hours in the MS760. He described the aircraft as "docile, fun and easy to fly." The stall is docile and straight ahead, although it will snap if cross controlled "like any other airplane" and "you'd have to do it deliberate." The flight instructor also said that the airplane flies "fine" with the ladder on the outside. He said that anyone who has much time in the airplane has done it once and "

Aircraft

Registration
N2TE
Reported as
Morane-Saulnier MS760 II
Category
Airplane
Serial number
005
Airframe hours
3,334
Engine
Turbomeca MARBORE VI, 1,060 lbs thrust, turbo jet
Damage
Destroyed
Fire
On-Ground
Flight
Personal · Part 91
Registered owner
Robert E. J. Morris
Airworthiness certificate
Standard, Utility
Last inspection
Annual · April 5, 1996 · 11 hours before
Departed
SNA · Santa Ana, CA
Airport
SNA · John Wayne, runway 19R, 5,700 × 150 ft, asphalt

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
48
Certificates
Commercial, Flight instructor
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--w/ waivers/lim
Seat
Right
Toxicology
Performed
Flight hours
2,169 total · 201 in this make and model · 1,868 as pilot in command · 48 in the last 90 days · 22 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
210° at 8 knots
Visibility
30 statute miles
Lowest ceiling
None
Temperature
63 °F, dew point 39 °F
Altimeter
30.00 inHg
Observed at
SNA, 1 nm away

Docket · 16

The files NTSB released with the investigation on September 9, 1997, on NTSB’s docket system: statements, records, photos and specialists’ reports.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.