WPR19LA078

NTSB accident investigation · Rans S12 · Socorro, NM · February 1, 2019

Accident · FatalClass 3 · LimitedFinal report
Date
February 1, 2019, 13:55 local (20:55 UTC)
Place
Socorro, NM
Injuries
1 fatal
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N536RHRans S12
Defining event
Takeoff: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
FAA FSDO
FAA report
20190201000489A
Case key
98939

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

A loss of control for reasons that could not be determined based on available evidence.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Not determinedNot determined › Not determined · Unknown/Not determinedHansen Ronald L RANS S-12XL: 1 caseAll aircraft: 2,247 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot departed on his third flight in the recently purchased experimental, amateur-built airplane and remained in the vicinity of the airport, where he completed several turn maneuvers. The airplane impacted a transient parking area at the airport and came to rest in an adjacent parking lot with substantial damage. There were no eyewitnesses to the accident. Examination of the wreckage revealed no evidence of preaccident mechanical malfunctions or anomalies that would have precluded normal operation. The pilot had previously communicated with the manufacturer about stability issues with the airplane. The manufacturer stated that the airplane required a total weight of 260 lbs in the seats to fly properly, and that the stability issues may be related to a lack of ballast. Two bags of ballast weight were found with the main wreckage and in the forward cabin area; however, the total weight of the ballast could not be determined due to loss of weight from damaged bags. Due to the loss of material from the ballast bags and the unknown amount of fuel onboard, the airplane’s weight and balance and center of gravity position at the time of the accident could not be determined. The nearest weather reporting station recorded wind from the south at 12 knots gusting to 20 knots. Although gusty wind conditions may have been present, the reason for the pilot’s loss of control of the airplane could not be determined based on the available information.

Factual 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 fallwithin 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.

Aircraft

Registration
N536RH
Reported as
Rans S12 (XL)
Category
Airplane, amateur-built
Serial number
11960757
Built
2000
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Unknown
Departed
ONM · Socorro, NM
Destination
ONM · Socorro, NM
Airport
ONM · Socorro Muni, runway 33, 5,841 × 75 ft, asphalt

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
75
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Flight hours
0 total · 0 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
160° at 12 knots, gusting 20
Visibility
10 statute miles
Lowest ceiling
None
Temperature
63 °F, dew point 32 °F
Altimeter
30.02 inHg
Observed at
KTCS, 51 nm away

Docket · 9

The files NTSB released with the investigation on April 12, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 7.1 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.