Letters: 06/05

Just read the April issue. Most flying magazines could take a lesson in how to fill 32 pages with useful information. I enjoyed the commentary/suggestion regarding a device in between a full-up glass cockpit and an EHSI. Larry Anglisanos article on the EHSIs was excellent and reading between the lines, seemed to be looking for the same thing.

A few years ago I read that Dynon had designed an all-electronic EFIS system that was relatively low cost for the homebuilt market (www.dynonavionics.com) . Why not the Dynon HSI to fill the obvious void? If there is a market and will someone step in to take the system through the FAA hoops?

John E. Horn
Via e-mail

Good question. Why not? Ron Ulbrich at Dynon told us the company has considered certification for its well-regarded instruments. However, its not far enough long with the idea to make any announcements.


Weather and PDAs
The PDA article in the April issue was very interesting. I have used both XM and WSI datalink weather.

Here are my observations: My WSI system in a certified installation using a MX-20 display in a Mooney Eagle. The hardware has been flawless in operation. WSI has a hole in its coverage area that seems to happen at the Colorado-Kansas state line. WSI uses one satellite with two antennas, one for east and one west coverage. There’s an area of low signal reception and the software seems to have a problem switching to the other coverage. I have gone for periods of 25 minutes without updates. They have been extremely courteous, but no fix seems to be available.

My XM system was with a notebook and the WxWorx receiver. I have also used XM with a PDA. The notebook PC was less prone to lock-up than the PDA, which on one flight refused to run the software, then, a couple of days later, worked perfectly. Since the problem with the PDA has not been recurring, no fix has been sought. However, there’s always the nagging wonder about when it will refuse to work in the future. I was surprised at how warm a notebook computer gets while sitting in your passengers lap. Not unbearable, just uncomfortable. My notebook was not bright enough to be seen in bright situations and too bright at night. I had an XM antenna fail and it was cheerfully and quickly replaced by the nice folks at WxWorx.

If you need to use computers or PDAs, just remember how much difficulty any Windows machine can present. There are no cigarette lighter adapters that stay properly plugged in when in turbulence. The WxWorx software was designed to operate on a touch screen computer. If you go this route, use a daylight-readable tablet. They are robust in construction and will give satisfactory results.

I find datalink weather to be essential. Safety of flight decisions can be made we’ll in advance and dangerous weather is most often easily circumnavigated. Both of these providers offer excellent service and support. If your flying is cross county, I recommend datalink for safety.

Bill Blackford
Lexington, Kentucky

WSIs Paul Devlin told us the perceived hole is actually a delay in switching between eastern and western beams, which have a significant overlap. Devlin said this is a known issue and WSI has a software fix available to owners of non-certified units. The same software upgrade will be available for certified units owners later this year.


VFLITE Rejoinder
Reference your article in the March 2005 issue comparing Garmins interactive training guide with the VFLITE system. I installed the CD on my computer at work and ran through it. Prior to this purchase, I had bought Garmins VCR tape on the 430 . The Garmin tape was $25 and very informative . The VFLITE product, for $180, covered the same material that Garmin did. I thought this CD was going to go more in-depth on the uses of the 430. I was wrong! After buying a new notebook computer for home use, I tried to install the VFLITE CD to no avail. After contacting Pegasus by e-mail, they informed me that I would be charged $10 to cover our costs editing the registration database in addition to processing and administration time. My advice: Save your money and buy the VCR tape for $25 and play it anywhere there’s a VCR.

John R. Jenkins
Via e-mail


Aztec Additions
Some corrections on your Aztec Used Aircraft Guide in the February issue. The statement that the E-model Aztec had another fuselage stretch and a bigger nose, is not correct. The C, D, E and F all have the same baggage compartment both in weight and volume. As for single-piece windshields, all Aztecs came from the factory with left and right two-piece windshields.

The nose extension on E and F models consists of a fiberglass cap-a longer and pointier nose-is actually a detriment from a radar standpoint. The increased taper of the added nose cone will not allow the 12-inch radar R/T unit, only the 10-inch version. The landing light is enclosed in the bottom of the extended nose, which is covered with a Plexiglas cover. The cover traps moisture, causing a radar return on the display. You can always ignore it as an anomaly, but one day it might be real.

The owners organization you are seeking for Aztecs is Diamond-Aire in Kalispell Montana. They also supply all the kits to make any old Aztec new again with one-piece windshields, tip tanks, dorsal fins and so on. They also have a user forum to answer any questions. (Website (www.geronimomontana.com/index.html) E-mail [email protected], web address www.diamondaire.com, phone 406-752-5092. The statement that airflow in the fuselage is from the tailcone forward is only true of the overhead vents, which should be closed for winter operation. The other missed opening is in the aft baggage compartment; cover it up and you’ll stay warm.

The latest AD 2005-01-10 is not a design fault. If you fail to put the clamp holding the exhaust pipe to the turbo exit on correctly, you can get a fire. The AD does nothing to prevent you from screwing up, it only addressed the melting of the remote oil tank, which is made of aluminum. The pipe can still fall out if not installed properly. The picture of the Aztec fuel tanks are depicted with the Apaches fuel selector system, misleading if you don’t know the difference .

With a fully equipped Aztec Turbo, built-in oxygen, deice, weather radar and Strike Finder, I have 3446 pounds empty weight with a 4500-pound zero-fuel weight. I can have 5.9 FAA passengers and fly for four hours. I don’t think this is much of a limitation.

Tom Baum
Via e-mail


In your recent article in respect to the Piper Aztec, you omitted to mention that there have been numerous accidents of Aztecs crashing as a result of fuel starvation. The following is the scenario: The Aztec has four fuel tanks; two on each side. The tanks are selected by pushing or pulling cables.

To select the outside tanks, the cable has to be pushed. During very cold weather, the cable will not push; the result is that half of the available fuel cannot be obtained. The result on a number of occasions has been fuel starvation and forced landings or crashes. There was one multi-fatality crash and several forced landings. Our office was professionally involved in one of the fatal cases.

To prevent repetition of the sad series of accidents, the pilot in command should always start out by utilizing the outside tanks and once the outside tanks are depleted, to pull cables to activate the inside tanks. Depleting the outside tanks first and then pulling to activate the inside tanks will reduce fuel exhaustion pressures and loss of lives and injuries.

Vern Schwab
Via e-mail


In our engine shop survey article in the April issue, the price given for the O-470U from Penn Yan Aero was incorrect. The actual price is $18,500.Poplar Grove Airmotive is located in north central Illinois, not central Illinois.