N8186KPiper PA-25 · 1960

On July 12, 2025, about 1322 mountain daylight time, a Piper PA-25, N8186K, was substantially damaged when it was involved in an accident near Hot Springs, South Dakota. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 glider aerotow flight.

The pilot of the glider being aerotowed reported that the accident occurred during his fourth flight of the day and a pre-takeoff briefing was performed before each aerotow. The glider pilot stated that on the accident flight, after liftoff, he kept the glider in a standard tow position while he contended with updrafts until the glider reached 1,500 ft agl at which point the glider was in a higher-than-normal tow position. The glider pilot radioed the towplane pilot that he was going to release from the tow rope. The glider pilot reportedly pulled the glider’s tow rope release knob twice but did not feel the rope disconnect. He subsequently determined the glider had separated from the tow rope, and he made an otherwise uneventful landing at the airport on runway 19.

A witness reported that the towplane and glider were in a climbing left turn and were about 500 to 600 ft agl when the glider appeared to get “extremely high” on the aerotow. The towplane pitched down, and the glider appeared to release from the tow rope. According to the witness, the towplane never recovered from the nose down attitude before it impacted terrain.

The towplane impacted terrain about one mile north of the departure end of runway 6 at the Hot Springs Municipal Airport, Hot Springs, South Dakota. The towplane accident site was located on an embankment of a gravel pit, and a postaccident fire ensued. The airplane impacted terrain in an estimated 50° nose-down pitch attitude. The relative angle between the airplane at impact and the 30° sloped embankment was about 100°.  The glider tow rope with a metal ring on each end was found at the accident site. The tow rope was about 200 ft in length and was constructed of a yellow hollow braid polypropylene rope.

All primary flight control surfaces and flaps were accounted for at the accident site and remained attached to their respective attachment points. All flight control cables were found attached to their respective flight control surfaces.

The towplane’s tow rope release latch and associated release cable were continuous from the cockpit to the latch mechanism at the tail. The latch was found in the open position, and the tow rope attachment ring was found on the ground about 15 ft from the latch. The rope extended in a south direction from the wreckage with portions suspended from tree branches. The towplane’s latch functioned normally when functionally tested.

The fixed 2-blade propeller remained attached to the engine crankshaft propeller flange. One blade exhibited an S-shaped bend and twisting near the blade tip. The leading edge exhibited leading edge polishing and chordwise scratch marks on the camber side. The other blade exhibited chordwise scratch marks on the camber side. Both blades had gouges in the leading edges. The cockpit throttle position was found to be near the idle power position, and the correlating throttle arm on the carburetor was found to be at the idle stop. The carburetor heat control arm was found in the off position. The mixture control was found in a mid-range setting. The engine crankshaft was rotated by turning the propeller by hand. No anomalies were found with the engine that would have precluded normal operation.

The glider came to rest in the grass next to the runway. A portion of yellow rope with a metal ring attached, consistent with a “weak link” portion of a glider tow rope, was found directly under the glider. This 7 ft long section of tow rope was found with a metal ring on one end and a broom straw separation on the eye splice end, as seen in figure 1. The metal ring was found directly under the glider’s tow hook latch.

Figure 1. Broken section of glider tow rope “weak link”.

The glider was moved to a hangar for further examination. During the examination, the tow hook release knob required about 22 lbs of force to release the latching mechanism. The sound of the release cable binding in its metal conduit was heard as the release handle was moved through its full travel (forward and aft). The latch mechanism otherwise functioned normally. An exemplary glider tow hook release knob was tested and required about 4 lbs of force applied to release the latching mechanism without any audible cable binding.

The towplane was recovered from the accident site to a secure location.