I was a CFI and student was ready for check ride. We went out for last flight review before his check ride, a confidence builder. We departed Boeing field and went West, to do air work and some T/O work at Bremerton (PWT), West of Seattle on the Olympic peninsula. After we finished the planned lesson, going back East toward Boeing Field (BFI) at about 1500 ft MSL, to stay below SeaTac (SEA) Class B, we passed by Vashon Muni airport, 2000' grass strips with trees all sides. It's on Vashon island in the Puget sound. You can see downtown Seattle from there. It is a challenge to land there with an engine.
I pulled the power to idle near Vashon and announced engine failure.
https://www.airnav.com/airport/2S1 [Read the additional Remarks, look at photo and terminal chart in link ]
Cub landing Vashon:
https://www.youtube.com/watch?v=-9aF7CuaSpU
Maule landing Vashon:
https://www.youtube.com/watch?v=Cjk36mDERtQ
Landing and taking off to the South:
https://www.youtube.com/watch?v=hVZVJNS9r2s
Vintage Waco Bi-Plane landing Vashon:
https://youtu.be/NFFdbmfY6EA
We just past Vashon to the North of the Field about to go over the Puget sound water. Without issue the student made a right turn back towards Vashon, setting up best glide, while trouble shooting. He was high on a LH dog leg to Runway 17. Using flaps, S-turns slipping he landed dead stick at Vashon to the South. I was proud. He did everything I taught him.
Now the problem (CFI in right seat me). C152's are not a power house, two adult men and full fuel we were under gross but not by much. Now don't judge, C152's are NOT not that big of a dog as you might think. At gross, SL, STD day they are typical or better than many light GA planes. However the C152 we were in that day was an Aerobat. It weights more than a regular C152, but we were still under gross. Unknown to me the airplane was about to have an engine overhaul. This 115HP Lyc O-235 was tired tired tired.
Although it was a sunny (for Seattle that is broken or overcast with holes) it had rained a lot the day before, a lot. Vashon is a grass strip and was a bit wet.
So we landed South and took off North on 35, winds were light but favored North T/O. Student taxis to get full length, configures 10 degree flaps, runs up, and starts take-off. The wet grass made acceleration sluggish, more than I expected. Between being near gross, the weak engine and warm humid field conditions (about 300 field Elev) it was struggling. The manual would be about 700 foot ground roll and 1300 foot to clear 50' obstacle. We had over 2000 feet. For ground roll on dry grass add 15%. about 800 feet, total 1400 feet to clear obstacle. The grass was not dry and the trees were above 50', but there was another factor.....
Student used good soft field technique, 10 degree flaps, broke ground, accelerated in ground effect, but he got too low and skipped off the ground at a wet spot scrubbing speed. We were back airborne and he rotated to Vx. When the student touched down during T/O run, I should have told him to reject the T/O. That was my second mistake. The first mistake was not considering field conditions and landing in the first place. Once we had the field made during practice engine out, we could have balk the landing and the lesson would have been effective.
So we now are climbing more than half way down the runway, committed. I could tell the trees at departure end were coming (even though I could not see them with the nose up). Keep in mind the proverbial AFM/POH "50' obstacle" can be 100' tall in Washington state.
I took the plane from the student (first and only time I urgently took a plane from a student in my CFI days). I banked left about 45 degree heading change, where there was a low spot in the tree tops. There is a house there. The clearing with tall trees displaced away from runway gave more room to climb than straight ahead. I am sure if the folks were home they were thrilled.
I got a few intermittent stall beeps in the turn, but we were climbing. This is where minimum controllable airspeed practice pays off. I watch the tree tops that were on the straight out departure out my right side window, slightly above our altitude. We climbed out safely on our left 45 departure. I accelerated to Vy, cleaned up, gave the plane back to student and calmly said, I'll explain on the ground. Pretty sure the right side of my face was sweating. "Let's go home" I said.
Student made a turn to East straight across the Puget sound to BFI at 1000' MSL to stay below SEA Class B. To get into BFI you have to drop to 800MSL to say under Bravo. This arrival from West you can't see Boeing Field (a very large airport), due to a ridge you cross at only a few 100' AGL. Once past the ridge at "the reservoir" you are mid-field 90 degrees from the downwind leg. Depending on wind you make a 90 degree turn for left or right down wind. We landed, safely on the ground at Boeing Field about 5 mins after our Vashon "Pucker-1" departure.
It was poor judgement to do a practice forced landing to full stop without planning. It was spontaneous, which is a bad thing in airplanes. The other C152's in the schools fleet with lighter basic empty weight, stronger engines, on a dry 2000 ft grass runway would be OK. However with all things considered, a C-152 does not leave a lot of extra room on short obstacle fields even with dry turf. This was way closer than I liked. I only went back to Vashon with students in C-172's and no recent rain, and only on request. I recall students were not allowed to go in there solo.
My student passed his Pvt check ride. (Proud to say all my students did.) As for the Aerobat, I saw her in the hanger next day with the engine off for an overhaul. That is when I realized it was a tired high time TBO engine. This was 27 years ago and still remember it. I looked at Photos of Vashon today. I'm glad to see it is still there, and they have clear cut the trees to the North end, and topped trees on the South end. They also built more hangers. I found 4 accidents in the last few years near or at Vashon, 3 related to takeoff and the soft (wet) runway. Here are two.
https://app.ntsb.gov/pdfgenerator/R...tID=20001208X09120&AKey=1&RType=HTML&IType=LA
https://app.ntsb.gov/pdfgenerator/R...tID=20120526X53325&AKey=1&RType=HTML&IType=CA
https://www.airport-data.com/images/airports/001/001120.jpg