History of Flight
On July 16, 2021, at about 1529 central daylight time, a Cessna P210N, registration N174R, departed Mustang Beach Airport (RAS) in Port Aransas, Texas, on runway 12 with winds from the southeast at about 10 knots. The flight was a business flight under Title 14 Code of Federal Regulations Part 91. After takeoff, the pilot contacted air traffic control (ATC) for an instrument flight rules clearance to Addison Airport (ADS) in Addison, Texas.
While climbing through 2,000 ft mean sea level, the pilot and passenger smelled an odor in the cabin and saw smoke emanating from the center control console. The pilot declared an emergency with ATC and requested landing at the nearest airport. At about 1517, the pilot reported a mechanical failure. ATC directed him to Rooke Field Airport (RFG) in Refugio, Texas, and cleared him to descend. At 1518, the airplane descended from 6,500 ft msl.
About 1519, the pilot had RFG in sight and was cleared for a visual approach. The airplane flew westbound past RFG about 4 miles, made a right turn back toward the airport, and entered a short left downwind leg before turning onto final approach for runway 32R.
The pilot was unable to extend the landing gear using the hydraulic power pack. He concluded the odor and smoke originated from a hydraulic power pack motor failure and attempted emergency gear extension using the hand pump. After numerous pumps, the green down-and-locked indicator did not illuminate. The pilot reported both main landing gear were extended but the nose gear likely was not fully locked. He continued the approach with partial flaps.
At 1528:41, the last ADS-B return was recorded over the displaced threshold for runway 32R at 150 ft msl (96 ft above the threshold). Calibrated airspeed was 83 knots, ground speed 99 knots, vertical speed -1,013 ft/min, and flight path angle -6.8°, consistent with a landing on runway 32R.
The pilot landed on the runway centerline, kept the nose gear off as long as possible, but upon contact the airplane veered right off the runway, rolled and skidded several hundred feet, and nosed over.
Aircraft Information
The Cessna P210N retractable landing gear is operated by an electrically-driven hydraulic power pack behind the cockpit control pedestal. Hydraulic pressure extends or retracts the gear and operates down locks. A pressure switch regulates pump motor power. During normal operation, the gear is held retracted by hydraulic pressure, and the power pack cycles on/off to maintain pressure.
The gear is extended via hydraulic pressure from the power pack. Main gear down locks are hydraulically actuated; the nose gear uses a mechanical hook. The power pack electrical circuit is protected by a 30-amp pull-off circuit breaker labeled GEAR PUMP. The pilot's operating handbook (POH) cautions to pull the circuit breaker if the pump continues running after gear cycle completion to prevent damage.
Hydraulic fluid level is checked via a dipstick/filler cap on the power pack, accessed behind a snap-out panel on the right side of the control pedestal. Fluid should be checked every 25 hours. If the power pack is inoperative, the gear can be extended using a hand-operated emergency hydraulic pump (if fluid is not completely lost), located on the cabin floor between the front seats.
Landing gear position is indicated by amber (up) and green (down and locked) lights near the selector handle. The green light has a push-to-test function; the amber light also has a push-to-test. Bulbs can be replaced in flight.
The Cessna P210 series Service Manual states that low hydraulic fluid can cause insufficient pressure and continuous power pack operation, potentially leading to electric motor failure and inability to extend gear via the power pack. The emergency hand pump draws fluid from a lower level in the reservoir and remains functional if fluid is not completely lost.
Meteorological Information
The nearest aviation weather station was at Aransas County Airport (RKP), Rockport, Texas, about 19.5 nautical miles southeast of the accident site. At 1453, surface winds at RKP were 150° at 9 knots with gusts to 18 knots. At 1553, winds were 170° at 8 knots with gusts to 15 knots. A High-Resolution Rapid Refresh (HRRR) model indicated surface wind at the accident site at 1500 as 168° at 13 knots.
Wreckage and Impact Information
A Federal Aviation Administration airworthiness inspector examined the airplane. Wheel marks on the runway and grass easement showed the airplane veered off the right side of runway 32R about midfield with all three landing gear extended. The airplane continued about 330 ft in the grass easement before the nose landing gear strut and nose wheel separated from the nose gear casting. It continued another 100 ft before nosing over and coming to rest inverted about 44 ft from the runway edge and about 2,880 ft from the displaced threshold. The fuselage, both wings, and empennage were substantially damaged.
No evidence of burnt wires, insulation, electrical arcing, or thermal damage to wiring between the hydraulic power pack and its circuit breaker was found. The 30-amp GEAR PUMP circuit breaker was found tripped/pulled. The green landing gear down-and-locked indicator did not initially illuminate when electric power was applied, but it illuminated after the bulb assembly was unscrewed and reinstalled.
The airplane was hoisted by a crane to test the landing gear system. With power on and the circuit breaker reset, the hydraulic power pack did not operate when the selector lever was cycled. Examination of the hydraulic power pack fluid reservoir revealed the fluid level was below the ADD level as indicated by the dipstick. No evidence of a leak was found. The landing gear extended into a down-and-locked position using the emergency hand pump.