Flying with inadequate briefing
While visiting a friend's aerodrome one day, I got chatting with a pilot, who I came to learn flew the jumpers at a nearby airport. He told me that they needed another pilot, and asked would I come out? Why not!
So I turned up the following weekend, and was promptly and enthusiastically greeted. He pointed to the rather tired looking Cessna 185, and asked if I would take a load of Jumpers. I asked if he wanted to check me out first. He said no, he had to go, I should just go on my own. I told him that I would like to fly a circuit by myself first. He said okay, but keep it short, they pay for the plane by the tenth of an hour!
I was rusty on taildragger, so I needed to refresh. A .2 (hours) circuit, and I felt okay flying it. When I got back there was a load of four jumpers ready to go. Okay…
I was given a parachute, which I had never before worn, got a very modest briefing on what to pull if I needed to. The chute was really uncomfortable, I disliked wearing it, but some rule said I had to. The main thrust of the briefing I was given was not about my 'chute, but what to do about the altitude sensitive automatic chute deployment if I had to bring a refuse to jump student back down with me. I never had to do that - I think they all thought that a parachute landing was more safe than landing back in a plane. There were occasions I thought they might be on to something!
On one of my first jump runs that day, the four jumpers climbed out one after another, but did not jump. They trailed from the wing strut. With four of them out there, now flying jump run at 55 knots(they had asked me to fly as slow as I would) I had full opposite rudder and aileron in to keep the plane straight as it approached the stall, suddenly one yelled "yahoo!" and they all let go. That poor plane, with all that control already applied, tumbled around so fast, I though that for sureI would hit the guys who'd just got out. I had no sense of where they were, or which way was up.
I recovered the plane, never having seen them, and started my descent back. As a part of this was a 2.5 to 3G spiral down, carrying some power so as to not shock cool the engine. I noticed that the plane really did not accelerate beyond 135 MPH during this descent. It should, 185's will pick up speed quite quickly when pointed down. Upon more close evaluation, I determined that once you reached 135 MPH, no matter how much faster you flew, the indicated airspeed would remain at 135. Once on the ground, I inquired. I was told “oh yeah, it does not read any higher that 135, we’ve been meaning to get it fixed”.
I indicated my expectation to see a recertified ASI before I flew again the following weekend - it was done. I later read that another local jump pilot, years earlier, had similarly tumbled his plane, and been thrown out - with no 'chute. Now I understood. The chute felt a little better after that.