Tales from The Cockpit

[ted.walsh]

I think the best part of the prep was listening to the radio recording of DC's penultimate run while also reading the transcript. it gave me a good insight into the boat handling at the interim speeds I thought were feasible on Fad. in the end we were pretty much spot on we just didnt have a bundle of margin left and so rightly called off trying to get then engine to pull 100% in favor getting the old girl to handle at slower speeds in a record breaking configuration and look good into the bargain...

[Canopener Al]

Thanks for the posts Ted, interesting reading on the issues of not a large supply of air and the issues that led to decisions being made in 1967. Yeph, the joys of controlling RPM vs Jet Pipe Temp with a hydro mechanical control system. Got the joys of seeing that on 2 Adour 104s hopefully coming up by the weeks end. The fuel system is similar that the Jockey can overtemp things if not taking care of watching the gauges and seeing if they respond.

[longarmedgibbon]

Ted in donalds book ‘ into the water barrier’ he said k7 pulled to one side when putting on the power due to the gyroscopic forces of the engine spinning, can you tell me if you experianced this your self? Ian lazenby

[Stuart Baker]

Joking apart - you can talk to yourself all you like Ted... it takes some proper planning, preparation and “right stuff” to do what you and Stew did, and I expect a fair amount of wear to the seat of your pants. Hats off to you both!

Hi Stuart, Was great to have you along for a day and to see the big boss on the tools and covered in grease. Sad that your inestimable contribution never officially took place but at least not a single drop of water made it past the grease-packed rudder post after you and the crew took it in hand that afternoon. Thanks for everything - you know what I mean.

A few years back my folks presented me with a picture of a much younger me, covered in muck and grease after rebuilding the suspension of an unworthy car. Underneath they had penned the inscription “never forget who you truly are”... Sadly, I get no chance to get mucky at work these days, but I look back fondly and really couldn’t stand by and let that one pass me by, so thanks for the chance to play!

Canopener Al - not sure why your Adours would overtemp... you must have the T6 limiter amp wired up or you’d revert to max trim. Is the limiter locked out during start? Not that I'd know anything about it of course

[kneeslider]

Loving the descriptions from Ted of how to handle an Orph'.

Puts you right there in the cockpit, reading that reminded me of hearing the RT playback from Andy Green at Black Rock in 1997.

I would dearly love to be in there at the controls, but like Bill, I know that there are others who would do a much better job, well at least without a shed load of training seat time!

Can't wait till next time, when I will be there to see it all happen!

[wbjohn]

Ted, re.
“we learned quickly that for whatever reason the trigger valve on the start cart can sick open and allow the start turbine to overspeed leading to Xena threatening situations. That along with damp from the lake freeing as all that rapidly expanding air removes the heat from the feed pipes and prevents the start team from breaking the coupling while I happily chug off oblivious with the inconvenience of two 50 litre air cylinders, a fishing boat, two extra unaccounted for passengers and the remainder of at least 1200 psi's worth of air still firmly attached to the side of our iconic craft because of an iced up coupling“
Did this all happen on week 2? as apart from 1 failed start due to failed fuse on the igniter circuit once yourself or Stew had released the air start button I had disconnected the power and air feed within 1.5 seconds everytime without incident for 7 days calmly and as we say in the workshop “perfect, but it will have to do” I was just wondering...

[ted.walsh]

Ted in Donalds book ‘ into the water barrier’ he said k7 pulled to one side when putting on the power due to the gyroscopic forces of the engine spinning, can you tell me if you experienced this your self? Ian lazenby

umm, it would be difficult for me to say with any certainty that there is precessional reactive force specifically when applying throttle based upon my current experience in her. What I can tell you about is the near lethal levels of sliding around the back of the boat displays once you are planing and go for power up! whether the overall gyro effect has be tamed a bit by the addition of the Gnat tail fin Ill not know unless Bill would like to knock up a 58' tail section to experiment with but she does tail slide around all over the place. whether this phenomenon is linked to the thrust line of the motor being higher than the CofG and causing the tail to come up at high power settings as the bows are pushed down Ill leave to the aero pundits but it doesn't half open your eyes the first time it starts skating about on you we went to Bute to learn and one of the features of the exercise was to discover how she handled in conditions far rougher than DC would of even got out of bed for. Our likelihood is that people will want to see her on the water, up on her points so this will need to happen in conditions that would previously be considered too marginal for any attempt so perhaps the observations of mine are new information or possibly just old information told a little differently. But blow me she slides around a lot if you let her, she does feel pretty smooth when doing it, like being on ice as DC commented once but I think the most alarming behaviour is when that great sail of a tail fin gets hit by a gust. Gusts are usually off the regular wind direction and on Bute they appeared to blow the back of the boat about into 100 mph tail slides the outcome of which I think would be difficult to predict if it were to get out of hand, though probably would be messy. The extra directional skeg was bolted on to the transom on the other side to the rudder at some point and having driven her I can see why as unchecked sliding must of added to pilot concern and workload quite a lot just at a time when you would want to have things start to smooth out. I can appreciate a desire of DC to try and get a handle on the situation. The big tail fin would of been a reasonable route to go down but the size of it can seriously wag the dog....

[longarmedgibbon]

Thanks for reply ted, very interesting. Ian lazenby

[Richie]

With the water being quite choppy on some days, what was your forward Viz like ?

[Renegadenemo]

Ted in donalds book ‘ into the water barrier’ he said k7 pulled to one side when putting on the power due to the gyroscopic forces of the engine spinning, can you tell me if you experianced this your self?

There's two effects from the spinning engine. One is the precession of the rotatives such that a right hand input will cause the nose to rise and vice-versa. The other is the torque reaction - the compressor spins one way so it wants to rotate the boat around it in the other direction. With the Orph' this lifts the left sponson and counters the weight imbalance. There's a great shot on the Sky doco of Ted killing the engine after a slow run and the left sponson dropping like a stone. Can't comment on the Beryl, which is what was fitted when Into The Water Barrier was written but assuming the weight and balance was correct the tendency would be to dig in one sponson as the torque reaction increased with the engine loads and that may well have caused the boat to pull to one side. How apparent any effect is in the cockpit nowadays, maybe Ted can tell us.