A Twin Otter can Porpoise too

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pelmet
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A Twin Otter can Porpoise too

Post by pelmet » Sun Jun 10, 2018 5:56 pm

Really bad.....

https://www.facebook.com/RunwayNewsline ... e_internal

Here is the view from the passenger cabin. Nice sound from the props on final.....brings back good memories(except for the ending).

https://www.youtube.com/watch?time_cont ... jzKLgVvMTs
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pelmet
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Re: A Twin Otter can Porpoise too

Post by pelmet » Sun Jun 10, 2018 6:28 pm

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pelmet
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Re: A Twin Otter can Porpoise too

Post by pelmet » Wed Jul 11, 2018 7:59 pm

PC-12 as well apparently. Don't push forward when you bounce.....

"C-GFLA, A Pilatus PC-12/45 aircraft was conducting a medical transport flight from Iqaluit, NU (CYFB) to Winnipeg/James Armstrong Richardson Intl, MB (CYWG). The aircraft was making a planned fuel stop in Coral Harbour, NU (CYZS) where the winds were reported to be 270 degrees at 15 knots. The touchdown on Runway 34T was firm and the aircraft bounced back into the air. The pilot flying, checked forward with the control column, and the nose-down pitching moment resulted in propeller contact with the runway surface. The aircraft was taxied to the apron. The crew did not note any unusual vibrations or engine parameters. The damage assessment is on-going."
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pelmet
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Re: A Twin Otter can Porpoise too

Post by pelmet » Thu Oct 25, 2018 8:13 pm

Looks like a Twin otter can porpoise on water too....

"C-FGQH, a float-equipped de Havilland DHC-6 aircraft operated by Harbour Air, was conducting flight HES2120 from Victoria Harbour, BC (CYWH) to Vancouver Harbour, BC (CYHC) with 2 pilots and 11 passengers on board. During the final approach at CYHC, the aircraft landed long due to traffic on the water. The aircraft contacted the water with a nose down attitude, which caused it to bounce. Reverse thrust was applied in an attempt to stabilize the aircraft; however, it bounced a second time before finally landing hard on the water. After landing, the flight crew heard noise and realized that something had broken. The aircraft was afloat, but the left float was loose. The pilot expedited the taxi to the dock, and contacted personnel ahead for assistance.

The operator’s maintenance discovered that the LH front float strut (PN C3UF1014-3) had failed, the front spreader bar had buckled, and the top of the float strut had punctured the fuselage in two places. There were no injuries or fire. The ELT did not activate."



Any thoughts?
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bobcaygeon
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Re: A Twin Otter can Porpoise too

Post by bobcaygeon » Fri Oct 26, 2018 6:49 am

pelmet wrote:
Thu Oct 25, 2018 8:13 pm
Looks like a Twin otter can porpoise on water too....

"C-FGQH, a float-equipped de Havilland DHC-6 aircraft operated by Harbour Air, was conducting flight HES2120 from Victoria Harbour, BC (CYWH) to Vancouver Harbour, BC (CYHC) with 2 pilots and 11 passengers on board. During the final approach at CYHC, the aircraft landed long due to traffic on the water. The aircraft contacted the water with a nose down attitude, which caused it to bounce. Reverse thrust was applied in an attempt to stabilize the aircraft; however, it bounced a second time before finally landing hard on the water. After landing, the flight crew heard noise and realized that something had broken. The aircraft was afloat, but the left float was loose. The pilot expedited the taxi to the dock, and contacted personnel ahead for assistance.

The operator’s maintenance discovered that the LH front float strut (PN C3UF1014-3) had failed, the front spreader bar had buckled, and the top of the float strut had punctured the fuselage in two places. There were no injuries or fire. The ELT did not activate."



Any thoughts?

I can verify that it porpoises pretty good on takeoff with CAP floats if you're newbie and you try and get on the step like your flying the 185. Hearing the fisherman in the back yelling "Yeehaw" confirms what you already know.
Power back to idle and try again.

I definitely liked flying it once I figured it out. I made the guy in the left seat laugh pretty hard and then bought a lot of beers.
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Last edited by bobcaygeon on Fri Oct 26, 2018 10:42 am, edited 1 time in total.

Meatservo
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Re: A Twin Otter can Porpoise too

Post by Meatservo » Fri Oct 26, 2018 10:09 am

While not difficult to master, a Twin Otter on CAP floats can take a little getting used to if the pilot is used to other types and/or different floats. Compared to other types of float, the CAP float has a smaller range of planing attitudes it will tolerate on the water. Often, mis-handling will be rewarded by porpoising, especially in a loaded plane.

One thing in particular that will result in a lot of porpoising on landing, if you're not prepared for it, is having a CofG that is too far aft.

The Twin Otter on floats is a very rewarding aeroplane to fly, at least in my experience, but there are some times it is less tolerant of mis-handling than say a Beaver or Otter.
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Dry Guy
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Re: A Twin Otter can Porpoise too

Post by Dry Guy » Fri Oct 26, 2018 10:12 am

Don't select reverse thrust while airborne would be my first one.
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Heliian
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Re: A Twin Otter can Porpoise too

Post by Heliian » Sat Oct 27, 2018 5:51 am

Reminds me of the yellowknife crash from 2011. Bounced and dug in but tried the go around.
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