Ditching a Cessna 150

"If a total loss of oil pressure is accompanied by a rise in oil temperature, there is good reason to suspect an engine failure is imminent" so sayeth the pilots operating handbook of the Cessna 150. La Porta lived this on Tuesday, July 26. 

He was flying a 150 from Tacoma Narrows Airport (KTIW) back to its base at King County International/Boeing Field (KBFI) when he noticed a drop in oil pressure. The route he was flying was one of the approved VFR approaches into KBFI and requires the aircraft to cross the Puget Sound at an altitude below 2,000 feet to avoid encroaching on the Class B airspace that protects Seattle-Tacoma International Airport (KSEA). When aircraft approach KBFI they must be below 1,100 feet to avoid the descending shelf of Class B airspace.

La Porta is a retired Boeing technician and a current CFI teaching out of KBFI. He was flying  an aircraft that belongs to Alternate Air, a flying club based at KBFI. He was very familiar with the airplane, as he flew it often with learners, but on this particular flight he was alone.

He'd flown to KTIW that day so a mechanic could address the seat rail airworthiness directive (AD) required every 100 hours for specific Cessna aircraft. According to the Federal Registry, the AD takes approximately an hour per seat as the rails, seat rail holes, seat pin engagement, seat rollers, washers, and axle bolts or bushings, wall thickness of the roller housing and the tang, and lock pin springs are inspected to ensure the seat will not slide out of position. Once the physical inspection for the AD is complied with, the mechanic signs off the work in the aircraft logbook.

"I had all the logbooks with me," La Porta noted. "And they went into the Sound with the airplane,"

Just before 4 p.m., the work was completed and La Porta, a pilot with 6,500 hours of experience, performed a preflight inspection. He had to return to KBFI because he had an appointment with a learner at 4:15 p.m. The flight back to KBFI takes approximately 10 to 15 minutes. During the inspection at KBFI, he had noted that the aircraft needed oil, so he added some, then carefully tightened the cap on the filler neck.

The winds were favoring takeoffs and landings to the north, so La Porta took off from Runway 35.  Pilots are careful to hug the shoreline of Vashon Island and to stay below the Class B airspace, which begins at 2,000 feet.

"I was just past the north tip of Vashon when I noticed the oil pressure was low and dropping," La Porta recalled, "and the oil temperature was rising." 

La Porta, who has been a pilot since 1974 and knows the airspace around Seattle very well, knew he was in trouble—especially if he tried to execute the VFR Vashon Arrival to KBFI, which would bring the aircraft down to 1,100 feet over houses, streets and the hilly terrain of West Seattle.

He asked the KBFI controller to allow him to deviate further north so that he could head for Alki Beach. Although it does have homes and businesses along the water, it is less populated than the route required by the Vashon Arrival. He estimated he was at an altitude of approximately 1,700 to 1,800 feet as he crossed the Sound.

"Essentially, I was a glider," he said.

There is a grass runway on Vashon Island that was behind him, but it is surrounded by tall trees and measures 2,001 feet by 60 feet, which can be challenging on a good day. As he was not having a good day, he dismissed the idea, and focused on going ahead.

"I knew that I did not want to go through Vashon Arrival because that would put me under the 1,1,00 foot shelf," La Porta explained. He noted that although he did not declare an emergency—he was too busy trying to find a place to put the aircraft down—and when he told ATC he had low oil pressure, they worked with him, understanding that he was having an issue.

As he crossed the water, La Porta managed the aircraft at best glide speed and continued troubleshooting. As he saw the oil temperature rise, the throttle lever became useless. Adjusting its position had no effect on engine power output, he said.

The controller cleared La Porta for a right turn to put him on a base leg for the runway, but La Porta replied, "I would love to but I can't. I don't have power anymore."

The right turn would have put him into a West Seattle neighborhood or possibly on State Highway 509 if he was lucky, but La Porta decided the safer thing to do for both him and people on the ground was to ditch the aircraft off Alki Beach.

"I had twenty gallons of fuel on board and I did not want to take a chance of fire or landing in a ravine with uneven terrain or landing on a road and dodging powerlines, and there were lots of house and people there, so I said instinctively, no, not going that way," he explained.

La Porta tightened the lap belt and cinched the shoulder harness as tightly as he could. "I could see the water getting closer and closer," he recalled. He did not lower the flaps to 40 degrees per the ditching instructions in the POH, but that may have been a blessing as the flaps would have possibly blocked his egress from the aircraft when the aircraft flipped over.

Ditching is something civilian pilots are required to learn about, but do not have the opportunity to practice. According to those who have experienced it in small aircraft, impact with the water is hard, like hitting cement, and very often the windscreen pops out and the pilot and front seat passenger get a face full of water like being hit by a firehose. The sudden deceleration throws them forward—if they are lucky, the shoulder harness keeps them from slamming into the panel.

"I closed my eyes at impact, and I felt the landing gear hit and the airplane went up on its nose, then went over on its back," he says. "I was upside down but couldn't tell inside the aircraft."

The next sensation La Porta had was the seatbelts pinning him in and water rushing into the airplane.

"The seatbelts saved my life. Without the shoulder harness I probably would have gone into the panel, but as I was hanging with my full body weight on the seatbelt, I could not get the belts to release until the airplane's tail settled into the water. I had one hand on the window and I was able to sort of stretch up and take a breath of air, and then I found the lap belt and was able to get it undone. I held on to the window as I released the shoulder harness and then I swam out of the window."

"There were three people in the water with me," he says. "There was a guy saying 'Give me your hand! Give me your hand!' and he pulled me along until my feet could touch the bottom, and then there was a woman who was a retired EMT who helped me. They asked if there was anyone else in the airplane and I said, ‘No.’"

La Porta warned his rescuers that he had been exposed to COVID a few days earlier, but they said that didn't make a difference as they helped him ashore.

The water temperature of the Puget Sound averages around 52 degrees Fahrenheit, and people who take unexpected dips in the water often experience rapid onset of hypothermia. The day La Porta went in, the Pacific Northwest was experiencing a heatwave. Outside temperatures were in the 90s. He was uninjured except for some scrapes from going out through the window.

Several people on the shore witnessed the ditching, he said. "One of them was a man who was an airline pilot for 15 years. He told me I did a good job and that there was white smoke training from the airplane."

A bystander on the beach captured video of La Porta's ditching—it made the television news both locally and nationally. Friends of La Porta recognized the aircraft and there were some frantic moments as calls to his cellphones went unanswered—until people realized the phones were likely onboard the aircraft with him.

"They're in the Sound, along with my kneeboard, which came flying off when I hit the water," he says. "I managed to get out with my headset, I have no idea how it became unplugged."

Within minutes, the local fire department and law enforcement were on scene. After being checked out by medical personnel, La Porta found himself on a conference call with the FAA and the National Transportation Safety Board—already starting the accident investigation.

Ditching is one of those exercises pilot's review but do not practice because it is normally not practical—you don't put a perfectly good airplane into the drink. La Porta noted that although ditching procedures for a 1970s-era Cessna 150 are printed in the POH, there is no mention that the seat belts can become jammed.

"I have been flying out of Boeing Field since 1975, I have done hundreds of crossings over the water and it didn't even occur to me that the seat belt would not release if there is pressure on it. I am carrying a seat belt cutter from now on and making sure my learners—and maybe everyone who is a passenger on the aircraft has one on all flights."

La Porta says he was lucky in many ways—he was able to ditch so close to shore, the shoulder harness kept him from going into the panel, and there were bystanders who took action to rescue him—and perhaps the most important thing, he says, was that he did not have a learner with him at the time, because if he had trouble getting his seat belt off, his learner probably would have as well, and one them might have drowned.

The aircraft was pulled from the water on Wednesday, July 27. Both the FAA and the NTSB will be examining the wreckage.

La Porta noted the windscreen was broken, but there did not appear to be extensive structural damage to the wings and empennage. The cause of the loss of oil pressure has not been determined, he said, noting that there are any number of reasons as mechanical things break. Ironically, the aircraft was coming up on its annual inspection, and there were plans to redo the radios and install a new engine on the airplane.

La Porta returned to the skies a few days later. He routinely flies several times a day. When asked if the accident has changed him, he replied he's now an advocate of shoulder harnesses, which are required in aircraft certified after December 2, 1986, but not before.

"If you don't have them in your airplane, get them retrofitted in," he said. "And add a seat belt cutter to your cockpit equipment."