Schempp-Hirth STANDARD CIRRUS N352D

Summary

On 11 April 2015 at about 22:25 local time, a Schempp-Hirth STANDARD CIRRUS registered N352D, operated by Prescott Soaring Society, was involved in an accident near Prescott Valley, Arizona, United States. One person was on board and one died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

11 April 2015 at 22:25

Classification

Accident

Location

Prescott Valley, Arizona, United States

Nearest airport

A.C. Goodwin Memorial Field (AZ86)

Coordinates

34.6808, -112.2969

Aircraft

Schempp-Hirth STANDARD CIRRUS

Registration

N352D

Category

Glider

Year built

1971

Operator

Prescott Soaring Society

Operating rule

Part 91: General Aviation

Purpose of flight

Glider Tow

Phase of flight

Not recorded

Route

Prescott Valley → Prescott Valley

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR15FA144

1 person died.

The pilot’s failure to maintain adequate airspeed and his exceedance of the glider’s critical angleofattack during the initial climb after a ground-tow launch, which resulted in an aerodynamic stall/spin.

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

Read the full NTSB narrative

A glider club member reported that the accident glider had been flown twice earlier in the day with no anomalies noted. He added that, before the accident flight, he advised the pilot that the glider had a "touchy elevator" and that things seemed to happen fast in a fiberglass glider. He observed the glider launch and noted that the glider appeared to be moving slowly with an increased angle-of-attack. When the glider reached about 800 ft above ground level, he observed it enter a left stall/spin before impact. The ground-tow winch operator stated that the accident pilot made a standard radio call that he was ready to launch and that he requested a reference speed of 65 mph. The operator then added power and saw what appeared to be a normal takeoff and initial climbout, during which the pilot called his speed as "65," which indicated that the winch power setting was as desired for the tow. The operator added that he heard the pilot call what sounded like "more power," which is not a standard call; a normal call would be one that indicated power needs, such as needed airspeed above or below the desired reference speed. The operator began to add additional power, but almost immediately thereafter, he saw the glider's nose drop as the glider entered a spin. Several other witnesses at the airport reported similar accounts of the accident sequence. Postaccident examination of the glider and the tow winch system revealed no anomalies that would have precluded normal operation. Therefore, based on the witness statements, it is likely that the pilot failed to maintain adequate airspeed during the initial climb and exceeded the glider's critical angle-of-attack, which resulted in an aerodynamic stall/spin and subsequent impact with terrain in a steep nose-down attitude.

Quoted verbatim from the NTSB record.