aera ERA

Interesting reading about the latest from Garmin in your December 2009 issue. A question from those of us that fly open cockpit: Will the touchscreen work with gloves on?

My iPhone wont. This could be another case where “improvements” take a whole class of user out of the market.

Gary Mitchell,
via e-mail

Yes, the aera will work with gloves on. Its resistive technology, not the capacitance technology used by the iPhone and others of its ilk. Although we didnt try the aera with gloves on, we used its motorcycle cousin, the zumo. Works fine with gloves.

Now that touchscreen entry is finally here, can you tap the course line on the new Garmin aera and drag/edit a segment in real time?

This would be great when ATC gives you a clearance change while IFR. No need to enter new fixes by keyboard… just drag your existing course line and have it snap to the nearest fix as when editing a line segment in a typical vector drawing program.

You didnt say, so Im guessing the answer is “no.” Or “not yet.”

Mike Palmer,
Glendale, Arizona

Well go with not yet. At press time, Garmin told us the aera doesnt currently have this precise capability, but that there might be a way to do it. When they let us know, we’ll let you know.

In the November 2009 sidebar on ADS-B, you said, “But the FAA doesnt like the idea of ADS-B parasites not transmitting, so it recently had ITT modify the transmission from ADS-B ground stations so they only broadcast information about traffic near participating aircraft. “

That may make a great conspiracy theory, but it is false. I worked as a private consultant to one of the firms that was bidding against ITT for the ADS-B contract. What you describe as “recently” was always part of the FAA requirement.

What is the point of transmitting in the blind when no participating aircraft are in the area? The ground-based transceivers receive traffic reports from both UAT and 1090ES and if traffic is detected using both frequencies at the same time and area, the GBT will duplicate the messages on the opposite frequency.

The GBT also receives transponder radar targets that are not participating in ADS-B and formats them into TIS-B transmissions. They are only sent, however, if there is an aircraft on the frequency with the capability to receive it. The ADS-B Out includes messages that define the participating aircrafts capabilities.

Unnecessary transmissions just congest the frequency, particularly on 1090ES. The FAA ADS-B design never considered “parasite” receivers (those receivers which do not have ADS-B Out). I spent considerable time discussing this with the FAA at the time. Traffic messages can be monitored with a “receiver only,” but they will not see all traffic and cannot control what traffic they will see.

John Collins,
Via e-mail

Your points are we’ll taken, but exactly what went on (and is going on) with ADS-B seems to depend on who you ask. Apparently, the final details werent actually final until they went into ITTs contract in 2008. Thats recent.

Some people say it was always the plan, others don’t. We had to pester the FAA for two weeks to finally get their side of the story and that was after deadline. At the least, the FAA is not happy about the parasite ADS-B systems and would like to see them all go away. Now.

Nice article on composite props in the December 2009 issue. I was wondering when articles like this would begin to hit the streets. Composite props are the current must-have accessory along with glass-panel displays and fluid de-ice systems.

You may want to check your source for price between the MT three-blade composite and the Hartzell three-blade composite. For the Cirrus SR22 (Hartzell item number J3F30500) the price is $29,229 while the MT is MTV-9-D-198-50 at $12,450.

This article also missed the owner feedback you normally ask for in advance and include in your work. I always look forward to that and missed it here. (Our Website includes several pages of owner quotes:

http://www.flight-resource.com/Testimonials.aspx

I checked for STCd applications of MT and Hartzell composite props. MT Props are STCd for install on nearly a thousand models equating to more than 100,000 currently flying aircraft worldwide. Hartzell composites have only a few STCs approved covering a much smaller population. I think readers should know this fact.

Last, the editorial comment that indicated a personal choice of Hartzell, all other things equal, may have been made with limited knowledge of what goes into the design of the MT blade.

If you cant make a trip to the MT design and manufacturing facility in Germany, you should take 16 minutes to watch the company video that shows the steps involved in the MT build. We have involved the engineering wizards of MT on several occasions to assist in design of a prop for a specific engine and are always impressed with the knowledge of the physical characteristics of every material used in the blades.

They know how to change, or design in, specific vibration frequency range absorbing characteristics, stiffness, inertial moment and peak efficiency at the RPMs we asked for. It is clear why the MT was the only prop that passed all the tests involved in selecting a prop for the diesel power plants. As the senior partner in the worlds largest volume MT distributor, yes, I am biased.

John Nielsen,
www.Flight-Resource.com

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