RANS S12

Full Narrative

On February 1, 2019, about 1355 mountain standard time, an experimental, amateur-built Rans S-12XL airplane, N536RH, was substantially damaged when it was involved in an accident near Socorro, New Mexico. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

Radar flight track data showed the airplane depart from runway 33 at Socorro Municipal Airport (ONM), Socorro, New Mexico. The airplane remained in the vicinity of the airport and completed multiple turns. The flight track ended about 1 mile northwest of the accident site. The airplane impacted a parked and unoccupied helicopter and a light pole, before it came to rest in a vacant parking lot at ONM. There were no witnesses to the accident. The pilot was transported to the hospital, and after seven days, died from his injuries.

Witnesses in a nearby building heard the airplane’s engine at “high rpm” and the airplane’s impact sequence shortly after.

According to a family member, the accident flight was the pilot’s third flight in the airplane, and he had a total flight time of about 25 minutes in the airplane. The pilot had replaced various tubing, replaced the sparkplugs, and rebuilt both carburetors soon after purchasing the airplane. The family member further stated that the pilot was experiencing weight and balance and stability issues and had communicated with the aircraft manufacturer on the horizontal stabilizer position.
In an email to the manufacturer, the pilot reported to a friend that during that second flight the horizontal stabilizer was positioned to the lowest position. In a response to the pilot’s email, the manufacturer stated that the airplane requires, “a total weight of 260 lbs in the seats to fly proper.” He further stated that, “it is not your stab setting it is a lack of ballast”; and “It is dangerous if out of CG.”
Examination of the wreckage revealed no evidence of preaccident mechanical malfunctions or anomalies that would have precluded normal operation. The horizontal stabilizer was found at its lowest position. Two bags of ballast weight were found with the main wreckage and in the forward cabin area. The total weight of the ballast could not be determined due to loss of material from the damaged bags.
According to the Pilot’s Operating Handbook, Chapter 4 - Weight and Balance:
If combined pilot and passenger weight are between 108 and 345 pounds that CG will be acceptable regardless of fuel conditions. However, flying at the aft CG limit requires adjustment of the horizontal stabilizer and hence as suggested by the test pilot, a solo pilot should us 50 or 75 pounds of ballast when operating the aircraft. Failure to do so will impose seven limits on the amount of nose down force available even with full forward stick. In any case, always test the authority of the elevators by doing a short crow hop. The center of gravity of the aircraft is the total moment divided by total weight and must fall within 69.5 and 76.5 inches (aft of datum). The CG envelope is graphed on the following page, a point inside the hatched region is safe with respect to loading.
An accurate weight and balance of the airplane could not be determined due to the unknown amount of fuel and damaged ballast bags onboard at the time of the accident.