Bolkow PHOEBUS N112AJ

Summary

On 17 July 2019 at about 19:25 local time, a Bolkow PHOEBUS registered N112AJ was involved in an accident near Alvord Desert, Oregon, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

17 July 2019 at 19:25

Classification

Accident

Location

Alvord Desert, Oregon, United States

Coordinates

42.5354, -118.4560

Aircraft

Bolkow PHOEBUS

Registration

N112AJ

Category

Glider

Year built

1967

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Glider Tow

Phase of flight

Not recorded

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

WPR19LA191

1 person died.

Pilot’s failure to properly respond to a slack towline during takeoff, which resulted in a loss of control of the glider.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The glider pilot took off utilizing the auto launch (vehicle-tow) method. Photos taken by a witness revealed that the glider overran the towline, which resulted in a slack towline. The glider then pitched up and, after reaching about 100-150 ft above ground level, rolled to the left and impacted terrain in a near vertical attitude. The tow vehicle driver stated that the truck had not yet accelerated to 60-65 mph needed for the release of the tow cable from inside the cockpit; instead, the truck had only accelerated to 55 mph before the spotter told the driver to stop as the glider impacted the terrain. A slack towline can be caused by a change in speed of either the glider or tow vehicle. If not corrected, a slack towline can result in the loss of control in flight. Also, a change in wind gradient can have a noticeable effect on a glider’s speed during ground launches. When a slack towline is encountered, a pilot should communicate with the tow vehicle to change speed, adjust pitch to control airspeed, or release the tow rope and land straight ahead. The investigation could not determine why the slack towline occurred. Nevertheless, the pilot did not follow recommended procedures for responding to a slack towline and subsequently lost control of the glider.

Quoted verbatim from the NTSB record.