Letters: July 2000

Diamond Star
I enjoyed reading your review of Diamonds new DA40 Star in the May issue. It was interesting to read your review side-by-side with the one in AOPA Pilot.

Your perceptions appeared to be 180 degrees apart on entry/exit ease, stall behavior and landing characteristics. Left me wondering whether you had flown the same airplane. In my view you missed the most glaring ergonomic faux pas in the Star cockpit, the stick. If they had gone with a side stick, or at least a yoke, that would have been fine. But that between-your-legs stick is a deal killer right there.

Despite its sleek appearance, the DA40 is neither a Pitts nor an Extra, its a travelling machine. My lap is valuable real estate. Thats where my kneeboard lives, with my flight log, pad for copying clearances and so on. The last thing I need encroaching into that space is a stick!

Also, how appropriate is it for me to expect my wife, or other non-flying passenger, to ride along with a phallic symbol sticking up between their legs, especially one which could have negative consequences if interfered with?

My preference would have been a single stick mounted between the seats, so the left-seater could fly right-handed, with dual power quadrants on each sidewall. Also, as for all those extra instrument holes, I believe Id use two of them for proper (read full-size) tach and MP/fuel flow gauges. Especially if it had those cartoonish, postage-stamp size Moritz guages.

Im not really old-fashioned, but I prefer my primary power control instruments to be up front, full-size, and readable. Also, Ill take my secondaries with numbers as well as color coded operating ranges, thank you.

Phill Probst
Columbia, Maryland

I enjoyed your excellent review of the Diamond DA40 Star, but wasput off by your over-the-top suggestion that airport neighbors who dont like airplane noise should move away and stop their whining….

Its apparent that non-pilots living near airports will always complain about noise and their complaints will increasingly be perceived as reasonable in the future. More to the point, noise is one of the more unpleasant aspects of flying to those of us who who love airplanes.

The serenade of a big radial engine is pure music to most pilots, at least from a distance. But spend eight hours in a Stearman without hearing protection, or work all day near an airport where F-16s are conducting lots of afterburner takeoffs, and youll reluctantly conclude that there can be too much of a good sound. If you polled your readers, Id bet youd find that most high-time pilots, even flyers who are only middle aged, suffer some hearing loss.

The trick is to find ways to reduce noise without reducing performance. Progress has been made in recent years and Im sure engineers will find more effective methods to mellow our airplanes music.

Charles Curtis
Tucson, Arizona

Gyro Feedback
Your article on low-cost back-up gyros sugar coats reality. All instrument pilots are familiar with the FAA version of gyro failure. The aircraft is cruising along with everything trimmed up and suddenly, black rubber covers are applied to the attitude and directional gyros to simulate failure.

The pilot demonstrates that he can keep flying under control using the turn coordinator and compass and then waddles through a VOR approach. This leads to a false sense of security that IFR gyro failure is no big deal. If we look at actual accidents, such as the tragic Doctor Jacoby Bonanza crash, the real world is more difficult. In this case, the gyro failure may have occurred during a takeoff into low IMC. Takeoff is a transient phase of flight where airspeed, attitude and altitude are changing rapidly.

Furthermore, departure clearances and physical obstructions often require low-altitude turns at 1000 feet above the airport. For a Bonanza, this means within a minute or so of leaving the ground.

In this transient environment, the pilots first critical task of just recognizing a gyro failure is difficult. Next, the pilot must sort out whats working and whats not. This is more difficult than the FAA-required demonstration and 99 percent of GA pilots have never been exposed to this situation.

Also, once a significant upset like a 60-degree steep turn has begun, restoring gyro suction or pressure wont automatically align an attitude gyro. What can we do to improve things?

First, for serious IFR, buy an electric back-up attitude gyro and learn to use the track function on your GPS as a back-up directional gyro. This gives the pilot a ready-to-go alternate gyro system immediately available and independent from the vacuum gyros. Second, get some simulator time, including realistic gyro failures or at least buy a PC flight simulator that can provide surprise failures.

Third, buy gyros with warning flags or at least put a low-vacuum warning light in the middle of the panel. Finally, lets use common sense about departing into very low ceilings. Sure, absurd FAA rules in Part 91 let a Bonanza take off in weather so bad a 777 jetliner operating under Part 121 would be grounded, but Jacoby and his wife and daughter would be alive and 22 people on the ground would not have been injured if the doctor had been able to sort out the gyro problem before he entered the clouds.

Frank Andrews
Everett, Washington

We agree with your observations. However, in the Jacoby crash, we dont yet know if gyro failure was the cause and we may never know. Gyro failure seems likely. Second, even in accidents where gyro failure is a likely cause, the lack of flight recorder or CVR data make the conclusion iffy at best.

The only convincing research weve seen on this subject was done by Richard Newman in 1980. His conclusions support your view only by degree. He rigged a 172 with a concealed vacuum cutoff valve and had subject pilots fly the airplane in simulated IMC. The pilots werent told the purpose of the research and the gyros were failed without their knowledge, in various phases of flight.

All of nine test subjects retained control of the airplane, although none flew a satisfactory VOR approach. Newman concluded all would have reached the airport under a ceiling of at least 1000 feet.

We still think this argues for back-up gyros of some kind, but the redundancy will be most useful on approaches in low weather. We suspect most current and competent instrument pilots can survive an attitude gyro failure in soft IFR or marginal VFR.