Vfs versus Vse

[C150J]

My new airplane has both, whereas my old one only indicated Vfto. I'm assuming Vfs approximates a best angle and se a best rate? The profiles make it seem that way (Vfs to MSA if you're worried about terrain), but I'm not so sure.


Thanks!

J.

 

[Polar742]

My new airplane has both, whereas my old one only indicated Vfto. I'm assuming Vfs approximates a best angle and se a best rate? The profiles make it seem that way (Vfs to MSA if you're worried about terrain), but I'm not so sure.


Thanks!

J.

The only plane I flew with Vfs spelled out as such was a clean Vyse speed.

 

[C150J]

The only plane I flew with Vfs spelled out as such was a clean Vyse speed.

Yeah, it's odd: if I'm truly worried about obstacles after bagging an engine, I'm thinking V2 as high as possible before cleaning up, then segueing to a final segment speed. I have to delve into SE drift-up now.

 

[Polar742]

Yeah, it's odd: if I'm truly worried about obstacles after bagging an engine, I'm thinking V2 as high as possible before cleaning up, then segueing to a final segment speed. I have to delve into SE drift-up now.

You're in a fairly big Biz jet right? Don't you guys have a performance/obstacle clearance program for TO?

 

[C150J]

We do, thank goodness! Our procedures do address flap retraction altitude as well. I'm just trying to understand what the heck our training vendor is addressing in their profiles. As you probably know, some of the vendors don't really address runway obstacle analysis appropriately.

 

[Mattio]

In the 170, Vfs is our final segment speed and thus best rate single engine, clean. If I'm remembering correctly, the FAA's Instrument Procedures Handbook has a good breakdown of the different segments and different terminology used for climb speeds.