Nov 2, 2008 · These winds can potentially disturb the airflow through the fenestron causing variations in fenestron thrust for a given pedal position. Relative wind velocity is as important as the azimuth in directing the main rotor vortices into the fenestron. Regardless of helicopter type, the retreating blade side is most susceptible to this interaction.

Oct 3, 2007 · Fenestron can produce the same total thrust for the same power as a tail rotor 30% larger, also by making the exit of the fan a bit divergent helps to expand the wake and the fenestron has no supporting fin blockage.

Jan 22, 2017 · Has anyone here flown a Fenestron and a non-Fenestron version? I am very curious of any noticeable differences in tail rotor authority / flight dynamics. Havent looked at the Fenstestron flight manual but I assume controllability margin (running out of …

Aug 2, 2008 · Pretty interesting things you can do when you don't have an exposed tail rotor. Not saying I would try this though, seems like a prime candidate for dynamic rollover.

Sep 16, 2005 · It just seemed that having the tail shrouded in the tail section (fenestron) would create less bite, but also less drag during forward flight,therefore increasing the speed. I also wonder if maybe the main rotor head and blades on the gazelle is less suseptible to retreating blade stall, and this is the secret to the aircrafts speed.

May 5, 2017 · If anyone has been paying attention the new Airbus H160 you will notice is has double horizontal stabilizers. I am pretty sure this is a new design as I've never seen it done before. Just curious about the aerodynamic advantages if any?

Feb 26, 2014 · It is basically a EC-120 clone without some of the advantages like the fenestron or large rear storage. Bell really screwed up by using a TurboMecca engine since that is one complaint against the 120 and they missed the opportunity to offer a …

Jul 25, 2015 · Hi allThis is my first post on this site. I am presently working on a board for selection of a light helicopter for basic helicopter training. In that the Airbus EC 120B and Bell Jetranger X are considered. The main rotor system of EC 120B(Spheriflex rotor), which I need to compare the advantages...

Sep 14, 2009 · More blades means you can either turn the rotor slower, or make it smaller, either way it will be quieter. Much of the noise from any helicopter comes from the tail rotor, fenestron, or whatever is back there. Most tail rotors turn pretty fast, and the tips are near the speed of sound. That makes for a lot of noise.

Sep 18, 2011 · I know the fenestron does not bite into the air nearly as well as open T/R. Probably a better rationalization is better support, especially for unscheduled issues. An airframe like the Eagle 407HP really was a good candidate because of it's operational profile brought it a lot closer to matching performance of a B3.