Coms

Why I fly

I just read Greg Brown’s October column (“Flying Carpet: Gift of Flight”). As I struggle with my studies for the CFI knowledge exam, occasionally thinking “I’ll never get this,” it is an article like this that reminds me how wonderful it is to share a flight with ground dwellers and give them an amazing and unforgettable experience. Thank you, Greg, for helping me remember #whyifly.

Gary Palmer
Ranchos Palos Verdes, California

Giving the slip

I ran across Jill W. Tallman’s short article on the turn-and-slip (needle-ball) versus the turn coordinator (“How It Works: Turn Coordinator,” January 2019 Flight Training). There were a few errors in there that might confuse students.

Both instruments indicate rate of turn, which is actually rate of yaw; i.e., how fast the airplane is turning about the vertical axis. The problem with the turn-and-slip indicator is that it does not indicate the beginning of a turn, when the airplane is rolling. Initially, the airplane is rolling without turning. A turn-and-slip instrument will stay centered during the roll so it doesn’t help you much with keeping the wings level should your attitude indicator fail.

Instrument designers, recognizing the limitation of the turn-and-slip, modified it slightly so that it would respond to both roll and yaw. Now when you start to roll, the turn coordinator will show a turn immediately, allowing the pilot to correct before the turn gets started. This is easier for most pilots to interpret should the attitude indicator fail.

So why do some aircraft still have a turn-and-slip? There are two major reasons. First, the turn-and-slip indicator is less “twitchy” in turbulence. Second, in the case of an upset that devolves into a spin, the turn-and-slip will always give correct information about how the airplane is turning, thus allowing a pilot to recover from a spin even if the other gyros have tumbled and are no longer providing accurate information. This is why military aircraft have kept the turn-and-slip.

Brian Lloyd
Spring Branch, Texas

Erratum

“What Am I: Check Your Six” (October 2019 Flight Training) incorrectly described the effect of pulling up on the elevator. It increases the tail’s downforce. Flight Training regrets the error.

We welcome your comments. Please email [email protected]. Letters will be edited for style and space.

Hot topic

“...low-time sport pilots are yet to be involved in a single Icon accident. Instead, it’s high-time, experienced pilots—many with advanced ratings—who are at fault....” bddy.me/2l8d772

Complacent pilots cause accidents. The plane is only as dangerous as the person at the controls. —Brian Thompson

Dave, I agree with your basic premise, but there is experience, and then there is experience. While most of these folks had a lot of time, few had much seaplane time. But, your point is well taken in the context that the scenarios of these accidents are as diverse as the pilots involved. The single thing I would have changed early on was their marketing, and they now have. It’s a gorgeous little airplane, but seaplanes love two things: lots of power and lots of wing, and the Icon has neither. It’ll be a great seaplane as long as pilots respect those limitations. —Michael Vivion

facebook.com/AOPAFlightTrainingMag