Amateur-built RS15 and Piper PA-25-150 accident near Ames, Iowa, July 18, 1995
On July 18, 1995 at about 6:40 pm local time, 2 aircraft, amateur-built RS15 (N964) and Piper PA-25-150 (N6084Z), were involved in the same accident near Ames, Iowa (Ames Municipal airport). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The glider pilot's inadequate preflight of the glider by failing to properly secure a push-pull tube to the glider's right ruddervator; and failure of both the glider pilot and the tow pilot to release the tow rope, which led to a stall of the tow airplane.
The glider pilot's inadequate preflight of the glider by failing to properly secure a push-pull tube to the glider's right ruddervator; and failure of both the glider pilot and the tow pilot to release the tow rope, which led to a stall of the tow airplane.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 18, 1995 · about 6:40 pm local time
- Place
- Ames, Iowa · Ames Municipal · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Amateur-built RS15
- Registration
- N964 · registry record · serial 16
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
- Aircraft 2
- Piper PA-25-150 · all PA-25-150s on the register
- Registration
- N6084Z · no longer on the register · serial 25-96
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative for the amateur-built RS15 final · quoted from the NTSB record
THE GLIDER PILOT STATED THAT AFTER HE COMPLETED HIS PREFLIGHT IN PREPARATION FOR LAUNCH, HE SECURED HIMSELF IN THE GLIDER AS THE TOW ROPE WAS CONNECTED. HOWEVER, HE COULD NOT RECALL ANY OF THE EVENTS THAT FOLLOWED, CONCERNING THE TAKEOFF ROLL OR ACCIDENT. THE TOW PILOT REPORTED THAT AFTER THE GLIDER WAS HOOKED UP TO THE TOW PLANE, A SIGNAL WAS PROVIDED TO BEGIN THE TAKEOFF ROLL. WITNESSES STATED THAT AS THE TOW AIRPLANE BEGAN THE TAKEOFF ROLL, THE GLIDER WAS HAVING DIRECTIONAL CONTROL PROBLEMS. THE TOW AIRPLANE LIFTED OFF AND CLIMBED ABOUT 50 TO 60 FEET ABOVE THE GROUND. THE TOW PILOT SAID THAT AT ABOUT THAT TIME, HE NOTED EXCESSIVE DRAG AND THE TOW AIRPLANE'S TAIL WAS PULLED DOWN DESPITE HIS USE OF FULL FORWARD ELEVATOR. SUBSEQUENTLY, THE GLIDER CARTWHEELED AND FLIPPED OVER, THE TOW ROPE FAILED, AND THE TOW AIRPLANE STALLED AND IMPACTED THE GROUND. POSTACCIDENT EXAMINATION REVEALED THE GLIDER'S RIGHT RUDDERVATOR WAS LOOSE AND WAS NOT PROPERLY CONNECTED TO THE PUSH-PULL TUBE. THE GLIDER PILOT STATED THAT HE DID NOT RECALL, BUT HE PROBABLY DID NOT DO A POSITIVE CONTROL CHECK OF THE RUDDERVATORS BEFORE THE LAUNCH. A WITNESS SAID HE OBSERVED THE GLIDER PILOT CLIMB INTO THE GLIDER'S COCKPIT AND WORK THE CONTROL STICK TO VERIFY AILERON AND RUDDERVATOR CONTROL, BUT HE DID NOT DO A POSITIVE CONTROL CHECK DURING HIS PREFLIGHT.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The NTSB's narrative for the Piper PA-25-150 final · quoted from the NTSB record
THE GLIDER PILOT STATED THAT AFTER HE COMPLETED HIS PREFLIGHT IN PREPARATION FOR LAUNCH, HE SECURED HIMSELF IN THE GLIDER AS THE TOW ROPE WAS CONNECTED. HOWEVER, HE COULD NOT RECALL ANY OF THE EVENTS THAT FOLLOWED, CONCERNING THE TAKEOFF ROLL OR ACCIDENT. THE TOW PILOT REPORTED THAT AFTER THE GLIDER WAS HOOKED UP TO THE TOW PLANE, A SIGNAL WAS PROVIDED TO BEGIN THE TAKEOFF ROLL. WITNESSES STATED THAT AS THE TOW AIRPLANE BEGAN THE TAKEOFF ROLL, THE GLIDER WAS HAVING DIRECTIONAL CONTROL PROBLEMS. THE TOW AIRPLANE LIFTED OFF AND CLIMBED ABOUT 50 TO 60 FEET ABOVE THE GROUND. THE TOW PILOT SAID THAT AT ABOUT THAT TIME, HE NOTED EXCESSIVE DRAG AND THE TOW AIRPLANE'S TAIL WAS PULLED DOWN DESPITE HIS USE OF FULL FORWARD ELEVATOR. SUBSEQUENTLY, THE GLIDER CARTWHEELED AND FLIPPED OVER, THE TOW ROPE FAILED, AND THE TOW AIRPLANE STALLED AND IMPACTED THE GROUND. POSTACCIDENT EXAMINATION REVEALED THE GLIDER'S RIGHT RUDDERVATOR WAS LOOSE AND WAS NOT PROPERLY CONNECTED TO THE PUSH-PULL TUBE. THE GLIDER PILOT STATED THAT HE DID NOT RECALL, BUT HE PROBABLY DID NOT DO A POSITIVE CONTROL CHECK OF THE RUDDERVATORS BEFORE THE LAUNCH. A WITNESS SAID HE OBSERVED THE GLIDER PILOT CLIMB INTO THE GLIDER'S COCKPIT AND WORK THE CONTROL STICK TO VERIFY AILERON AND RUDDERVATOR CONTROL, BUT HE DID NOT DO A POSITIVE CONTROL CHECK DURING HIS PREFLIGHT.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record for the amateur-built RS15 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land; single-engine sea; instrument: airplane; rotorcraft: glider
- Flight time: 1,618 hours in all; 1 in this make and model; 11 in the last 90 days; 1,511 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Last inspection: annual inspection
- Maximum gross weight: 940 lb
- Seats: 1
- Landing gear: fixed
- Engine: (type not recorded); 0 hours total
The flight
- Departed from: AMW at 6:40 pm
- Flight plan: none
- Runway 31, 1,800 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 310° at 6 knots
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 55°F (13°C)
- Altimeter: 30.00 inHg
- Observation at 6:50 pm from DSM, 27 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
The factual record for the Piper PA-25-150 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land; rotorcraft: glider
- Flight time: 1,200 hours in all; 16 in this make and model; 6 in the last 90 days; 4 in the last 30 days; 1,175 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 3,193 hours
- Last inspection: annual inspection, August 2, 1995; 24 hours since
- Maximum gross weight: 2,300 lb
- Seats: 1
- Landing gear: fixed
- Engine: Lycoming O-320-A2A (piston); 0 hours total
The flight
- Departed from: AMW at 6:40 pm
- Flight plan: none
- Runway 31, 1,800 ft by 100 ft
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.