Enter your keyword

iFLY Main Foil Differential Technology – MDT Foil Control – high Performance sailing

iFLY15 Blog | stay tuned

iFLY Main Foil Differential Technology – MDT Foil Control – high Performance sailing

iFLY Main Foil Differential Technology – MDT Foil Control – high Performance sailing

Active flight assistanceadjustable Rake while sailing

Advanced Rake Control for the experienced, performance-oriented Catamaran sailor / pro sailor


MDT available as a feature on the iFLY RAZZOR Pro or as an upgrade on the iFLY15 One Design.

Main Foil Differential Technology – MDT is the key to maximum performance with the iFLY. Especially when foiling on upwind courses, the speeds can be increased by up to 25%.

When does the Main foil Differential / Rake Control make sense?

MDT is valuable whenever the wind pressure would otherwise be too big to the flight attitude. In particular, it allows e.g. to sail in stronger winds. With XXL sails, it is an ideal addition, even in light winds.

How does the main foil differential work?

With MDT, the sailor controls the angle of attack of the entire windward foil. With the downforce that can be precisely adjusted in this way, you can sail even harder. The mainsheet stays tight longer. The iFLY Main Foil Differential – MDT can be easily operated using a sheet from the trapeze and the foil can be trimmed actively.

MDT and FlySafe® Foil Control – Active and passive flight assistance

MDT extends the FlySafe® dynamic foil control, which has been tried and tested for many years and acts on the tail units. The “flight flaps” are controlled like in an airplane and dynamically passively regulated. The MDT is actively operated by the sailor. The two systems FlySafe® and MDT work hand in hand.

This not only ensures a superior, stable flight attitude, but also increases the urgently needed righting moment, e.g. to hold high wind forces.

The weight trimming by the sailor is increased, i.e. the weight forces are increased to the maximum. This allows full pressure to be maintained in the sail instead of releasing the mainsheet.

Why Main foil Differential?
Main foil versus rudder foil differential

The differential adjustment of the main foils is considerably more effective and therefore works faster than adjusting the much smaller rudder foils. With the iFLY, by adjusting the inclination of the entire main foil, the foil is trimmed for downforce and thus causes an enormous increase in the righting moment. (Link article Americas cup)

For whom is the main foil differential suitable?

In addition to the increase in performance through MDT, the technology can also be of interest to sailors who are not primarily performance-oriented. If he prefers to sit on the trampoline instead of sailing on a trapeze.

Thanks to the extra righting moment, good performance values are achieved despite sitting on the trampoline.

Big rigs when foiling:

The role played by MDT in the “iFLY Open Class” with the “IFLY RAZZOR Pro” model is extremely important: only with MDT can the large XXL rigs of the iFLY RAZZOR Pro with 8.5m and 9m long masts be used and controlled in a meaningful way. Without MDT, the sailing boat would quickly become “overpowered” and the sailor would hardly be able to control it.

MDT in light wind

We have tested XXL rigs extensively and observed large increases in performance even in lighter breezes, but only in combination with MDT. Without MDT, the standard iFLY15 rig is recommended to be sailed with the 7.5m mast of the “iFLY One Design Class”.

Sailing the iFLY RAZZOR Pro with MDT and XXL rigs makes the boat more powerful (especially in light winds) but also more challenging. The iFLY RAZZOR Pro is for the experienced, performance-oriented sailor.

#We love Speed #join the adventure