The flight crew is often the last safety net when things go wrong, making their failures an easy target for us to point at. After all, if the pilot can be retrained or is no longer flying, then we can consider the problem solved. This allows training deficiencies, operational issues and poor maintenance to be swept under the carpet, an ongoing temptation as they are much more difficult to solve. It’s handy to have someone to blame and that is why we need to be careful not to fall into that trap.

However in general aviation cases, it’s possible for an entire sequence of events to be laid at the feet of the private pilot. This fatal crash in 2017 is one such case which appears to have been totally avoidable if the pilot had been willing to slow down and listen.

The pilot was extremely experienced: he held an airline transport pilot certificate with 33,467 flight hours, rated for single- and multi-engine land and single-engine sea planes. He was an FAA pilot examiner for over 46 years and had certified nearly 3,000 pilots. In 2013, he was inducted into the Minnesota Aviation Hall of Fame. The only black mark in his paperwork was that his medical had expired the year before. An FAA checklist of documentation required for a medical certificate was found with his paperwork, however it was incomplete and unsigned.

He was the sole pilot and owner of the accident aircraft, an Aerofab Inc. Lake LA-4-250 Renegade amphibious aircraft built in 1983, registration N1400P. The six-seater Lake Renegade set half a dozen new records for single-engine amphibians in the late 1980s, including world records for altitude, sustained flight and sustained flight at altitude. Lake Amphibious Seaplanes founders came from Republic and Grumman Corporation and claim to have developed the only single-engine, boat-hulled amphibian in production in the world today.

EAA AirVenture Oshkosh is an annual fly-in convention held every summer in Oshkosh, Wisconsin, a small town on the banks of Lake Winnebago. In 2017, it ran for ten days, from the 21st to the 30th of July. AirVenture is one of the top events for the aviation community in the US and afterwards, the Chairman said it had been incredible.

From the U.S. Navy Blue Angels and Apollo reunion, to new aviation innovations on display and two B-29s flying formation as part of 75 years of bombers on parade, it was a week filled with only-at-Oshkosh moments. You could feel the energy as thousands of airplanes arrived early and stayed longer, pushing aircraft camping to capacity for most of the event. The aviators and enthusiasts who attended were engaged, eager, and passionate, demonstrating how Oshkosh is the best example of why general aviation is so vitally important to the country. I believe it’s the best AirVenture week that I’ve ever seen.”

This video shows the seaplanes at EAA Airventure including the accident aircraft (N1400P) at the 1:10 point:

That week, over 10,000 aircraft flew in for the event and Wittman Regional Airport, the centre of the event, had 17,223 aircraft operations over the ten-day event, averaging 123 take-offs and landings per hour. The other airports hosting the event include Pioneer Airport for helicopters and airships, Ultralight Fun Fly Zone for ultralights, homebuilt rotorcraft and hot air balloons and Vette/Blust Seaplane Base on Lake Winnebago for seaplanes.

On the 27th of July 2017, the owner of the Lake Renegade decided to fly to the Vette/Blust Seaplane Base to attend AirVenture with two passengers. One of the passengers was a flight instructor with 3,000 hours flight time, with 1,600 hours instruction and 150 hours on type. He said that he had trained the pilot for seaplane flights and had personally conducted about a hundred water landings in Lake Renegade aircraft. The other passenger did not have piloting experience.

The weather that day was clear with heavy swells at Lake Winnebago. The Lake Renegade landed in a bay south of the sea base and began to taxi north along the shore towards the Seaplane Base. After a few minutes, the pilot contacted the base to say that they were taking in water and needed help.

Five boats and ten volunteers were dispatched to help the pilot but it seems like the entire base mobilised to help. The harbour master followed in his tow boat and saw the left wing was low in the water and heavy. When the Seaplane Base Chairman arrived, he saw the aircraft drifting towards shore, just 30 feet from the rocky shoreline. The volunteers manoeuvred the aircraft away from the rocks. Then a tow boat positioned itself to the right of the Lake Renegade and a passenger held down the wing in order to prevent the left wing from dipping into the lake. Like this, they were able to tow the aircraft into the Seaplane base.

The left wing sponson, a buoyancy casing that extends from the hull like a short wing in order to increase stability on water, had been taking on water after landing. They pulled the Lake Renegade’s left sponson onto the dock, where the pilot removed a plug and drained a large amount of water. Then the harbour master pulled the aircraft to a mooring plug to park.

The pilot and his two passengers left and returned about two hours later. A volunteer helping with AirVenture took the pilot to his mooring.

The volunteer boatman said that the pilot boarded the Lake Renegade and then proceeded to start the engine without untying the mooring plug first. The aircraft began to turn in a circle and the boatman stopped the pilot, asking what he was trying to do.

The pilot became argumentative, declaring “You can’t prevent me from leaving with my aircraft!”

The boatman said he that he just wanted to help and that the pilot wasn’t going to be able to leave unless he untied the aircraft from the buoy. Once the Lake Renegade was untied, the pilot asked to be towed to the ramp to drain his sponson. There, he asked for a water pump but when he was asked why — and if he had water in the aircraft hull — the pilot said no and proceeded to drain the water out of the sponson manually. He then opened the drain valve for the fuel tank in the left sponson and began draining the fuel into the water. The harbour master found a bucket and asked him to drain the fuel into that. At the same time, some of the Seabase personnel noticed that there was an inspection cover missing underneath the left wing, outboard of the sponson.

The pilot emptied the left sponson fuel tank until it ran dry, about four to five gallons of fuel. He then closed the drain and asked to leave the base.

The conditions at Lake Winnebago had deteriorated in the time that the pilot and his passengers were at Oshkosh. By now, the waves were 18 to 24 inches high (around half a metre) and the staff considered that the water conditions were too rough for the seaplane. The Lake Renegade has a maximum demonstrated wave height of 18 inches. Three pilot briefers attempted to convince the pilot that flying out would be unsafe in the heavy waves conditions. When the pilot insisted that he still wanted to leave, they called the Seaplane Base Chairman.

The chairman explained that they were concerned about the pilot’s departure because of the rough waves and convinced the pilot to join him on a boat to check the water condition in the outer bay. As they motored to the outer bay, the pilot agreed that the waves were too big and the water conditions were were unacceptable. But then, to everyone’s surprise, he said that he would simply take off parallel to the swells.

The chairman pointed out that this would mean a downwind take-off (instead of taking off into the wind to increase take-off performance). He wrote later that he told the pilot: “You will NEVER get airborne with a Lake, with full fuel, three passengers, heavy wave conditions and downwind – NEVER!”

The pilot disagreed about the direction of the wind claiming it was clearly blowing from the northwest, the opposite direction. As they returned to the protected bay of the Seaplane base, the chairman pointed out that every aircraft was pointing into the wind, showing the wind was coming from south-southeast. All of the seapbase personnel tried explain to the pilot that they were trying to help him but the pilot simply told them to take him back to his aircraft.

Once back at the base, the chairman found another Lake Renegade pilot who also agreed that the water conditions were too rough for take-off. The pilot was offered assistance in finding lodging for the night but he insisted that he was going to load his passengers and depart.

After the accident, the flight instructor, the only survivor of the crash, said that as far as he was aware, the pilot received a briefing from the dock managers and then went with the briefers for a visual look at the water conditions, where he decided it was safe. However, the observers at the sea base disagreed.

The pilot initially agreed that the water conditions were too poor; however, he later elected to depart with a tailwind despite the unsuitable water conditions and strong objections of seaplane base staff and other seaplane pilots. According to witnesses, the pilot demonstrated a strong resistance to the advice of those who he interacted with throughout the afternoon.

One of the sea base staff reminded the pilot of the missing inspection cover underneath the left wing, without which the aircraft was not airworthy. The harbour master towed the aircraft to a repair dock where they found a scrap piece of aluminium which the pilot duct taped to the hole as a temporary field repair. The harbour master recalled that the aircraft sat normally in the water, with no sign that the left sponson was still taking on water. He towed the aircraft from the dock to “the cut”, a narrow gap leading from the base to the bay. The pilot said he was going to start the engine and the harbour master held up one finger to signal that he should wait until he’d towed them into the bay. The pilot repeatedly asked to start his engine and the harbourmaster asked him to wait.

At the outer bay, the pilot started the engine the moment that the harbour master disconnected the tow ropes. He immediately applied full power for take-off.

The chairman saw the initial take-off run, which he said was with a 90° cross wind. About halfway through the take-off run, the pilot changed direction, now heading northwest with a direct tailwind. Those watching from the docks noticed with concern that the flaps were still up.

The aircraft continued to accelerate for about sixty seconds, when the aircraft bounced, beginning to “porpoise” in the high waves.

A Lake flight instructor told the investigators that a water take off with a two-foot sea state (waves at 24 inches) is unadvisable unless the pilot is very experienced. A rule of thumb taught to new pilots is to retard the throttle immediately during water take off if you feel a thump as the fuselage makes contact with the water, allowing the aircraft to settle. More experienced pilots, he said, might not retard the throttle until they felt two or even three thumps while porpoising.

The pilot did not retard the throttle. After the third porpoise, the nose rose steeply out of the water and then rolled over to the left. The left wing caught the water, spinning the aircraft by 180°. The nose dipped into the water and started to sink.

The engine remained at full power until it was submerged into the lake.

A witness told local media, “We saw the plane come out of the seaplane base, and it looked like it was having some trouble getting up. We were saying, ‘Come on little plane you can do it,’ then all of a sudden we realized it had just gone down.”

The aircraft came to rest in about 15 feet of water with the right wing partially buried in the mud. Everyone in the area rushed to the scene to attempt to offer assistance. As the first responders arrived at the crash site, they saw a man pull himself out of the aircraft and inflate his life jacket. It was the flight instructor: the pilot and the passenger were still inside.

The harbour master jumped into the water and forced open the left cabin door, where he found the pilot unresponsive. Someone passed him a knife to cut the pilot free of the seat belt and he pulled the unconscious man to the response boat, where they administered CPR. The harbour master returned to the wreck where the divers were attempting to release the passenger from the back seat. It took two of them to pull her free, and she was also taken to the response boat where CPR was begun. Both were taken to hospital in critical condition. The passenger died the following day and pilot a few days later.

The wreckage was recovered four days later for examination.

Both left and right wing spars exhibited buckling. The right wingtip was bent upward into the right aileron and the fuselage exhibited buckling deformation immediately forward of the empennage. Continuity was verified between all control surfaces and the cockpit flight controls. The landing gear handle was in the UP position and the landing gear were found retracted. The flap lever was found in the UP position and the flaps were retracted.

No preimpact anomalies were noted that would have prevented normal operation of the airplane or engine.

The flight instructor’s recollection of the chain of events seems relatively clear. He said that the pilot started a powered-up circling take-off in the bay. The plane broke water, he said, and then hit some waves. From his seat, it seemed that after bouncing about three times, the right sponson caught a wave and sucked it down, at which point the plane flipped on its side with the right wing on the water. The right door popped open on impact but by then he was underwater and it was difficult to push the door open against the water rushing in. Once he got out of the aircraft, he said he looked through the left-side window and saw an air cavity in the cockpit but, shortly after he escaped, the plane sank.

He was sure that the pilot had performed the preflight checklist before taking off. He also said that he remembered that the pilot had called out that the flaps were down (set for take-off) as a part of his checklist.

Witnesses distinctly recalled that the flaps were not down for the take-off, specifically because this seemed odd. An examination of the wreckage showed that the flap selector lever was in the UP position. And later in his statement, the flight instructor also said that in the Lake Renegade, the flaps did not have to be extended for take-off.

This is not true. The Airplane Flight Manual (AFM) for the Lake L-250 clearly states that flaps are used for all takeoffs and landings. Step 14 of the Before Takeoff checklist is to verify that the wing flaps are down. In the cockpit, a printed checklist was clipped to the instrument panel which also included the clear requirement to verify that flaps were set DOWN for take-off and landing.

As a result of the flight instructor’s statement, bearing in mind that he also said he trained the pilot for seaplane flight, it’s not clear whether the pilot forgot to set the flaps for take-off, simply repeating “down” out of habit as he rushed through the checklist, or if he intentionally did not set them in hopes that it would help him with the tailwind take-off over the swells.

The NTSB summarised the sequence of events:

…the circumstances of the accident are consistent with the pilot rushing to depart and failing to ensure the airplane was properly configured with flaps extended before taking off. Additionally, the pilot elected to take off with unfavorable water and wind conditions despite the advice from other pilots that he not do so. The pilot’s decision to takeoff with unfavorable water conditions and a tailwind, combined with his failure to lower the flaps for takeoff, likely contributed to the airplane stalling as soon as it became airborne and resulted in a loss of control

In other words, he never had enough airspeed or angle of attack to take off. When he attempted to force the aircraft out of the water by pulling back on the controls, the wing stalled immediately.

Probable Cause

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot’s failure to properly configure the airplane for takeoff and his decision to takeoff with a
tailwind in unfavorable water conditions, which resulted in the airplane entering an aerodynamic
stall and the pilot losing control.

AOPA’s Air Safety Institute have done quite a good recreation of this crash with quotes from the witnesses, photographs from the site and the actual video taken of the take-off.

The staff and volunteers at the Airbase are all very clear that they literally begged him not to fly in these conditions. The pilot may have considered the rough conditions to be borderline and it’s true that at least one Lake pilot at the site stated that he thought it wasn’t outside of the ability of a highly experienced pilot. However, the pilot that day wasn’t highly experienced in seaplanes and he chose to risk a tailwind take-off in an aircraft that had required a tow a few hours before because it had taken on water. In his rush to leave, he either forgot or chose not to configure the aircraft correctly for take-off. It is very difficult to interpret his actions as anything other than reckless.