BEST OF RC hydrofoil trimaran

BEST OF RC hydrofoil trimaran with onboard and offboard perspectives. I still got problems with flow separation / cavitation at the main foils...

Category:

Science & Technology

Tags:

• RC
• hydrofoil
• rc hydrofoil
• trimaran
• flying
• boat
• foiler
• foil
• hydro
• onboard
• hydroptere
• fast
• swan
• underwater
• submarine

[realslim]

Do you use an attitude control mechanism for the rudder foil, or is it governed by the overall attitude state of the craft as determined by the main foils?

[maedefly]

@realslim

No, I didn't use a control mechanism in this video. It's just the setup over all the foils which makes it stable. But it was quite difficult to find the narrow equilibrium. Adjustments need to be made in fractions of a degree.

I tried everything from passive to active (RC controlled) attitude control, both on the front and rear foils (all T shaped). But without success. They produced just too much drag....

Thanks for your feedback!

[realslim]

It's possible that it's cavitation at 2:20, but it's more likely ventilation, which occurs when surface air is pulled down the foil, then rockets back out, spraying all that water up with it. Ventilation is the major downfall of surface-piercing foils.

The ventilation problem can be solved with fences on the foils - small perpendicular blades attached to the foils that prevent the air from attaching to the foil. Similar tech is used on outboards to keep surface air away from the prop.

[maedefly]

@realslim Thanks for your advise!

I will surely try that...

[realslim]

Dude, this is awesome. Must be watched in HD - I love all the footage, especially the on-board and submersed stuff. This is an outstanding contribution to foilers everywhere.

I'm really glad to see you opted for only the surface-piercing foils on the amas - that fully submerged T-foil on your center hull in other videos produced some nice lift, but too much in some cases, it seemed.