September 2005 Issue

Unicom: 09/05

Got Game?
I just finished reading the article “Big City IFR” (July 2005). It was enjoyable and very timely. I recently took my F33A Bonanza into Chicago Midway (twice in two days). It was, well, an interesting experience.

I earned my Instrument ticket last fall and frequently travel into controlled airports within Class B, C and D airspace. But even with my experience at airports with high traffic volume, it’s just not the same as airports with high volumes of airliner traffic.

It was clear as I approached Chicago airspace that I was the small fish that was going to mess up everyone’s already busy day. It was obvious (and I somewhat expected it) that I would be worked into the flow as long as it had no impact on the big guys. That translated to a maximum impact on me: many vectors, higher than normal approach speeds and a heck of a final approach.

My biggest goof was switching to the ground control frequency once clear of Runway 22R without being told by the tower to do so. I sat for some time waiting to get a word in edgewise with the ground controller, only to find out that the tower was still trying to talk to me on the other frequency. (I sensed a small amount of irritation from them on that one.)

But as you recommend in the article, I did plan the trip well before departure. Knowing (and filing) the published arrivals made the inbound trip fairly mundane with regard to revised clearances and unexpected requests. Having all of the charts out, unfolded and marked was a must. But even with all of that preparation, that type of environment is just a different animal. There is no planning or training that can compare to actually “doing it.”

I learned from it. I’m a better pilot because of it. But I still get that little knot in my stomach every time I relive the experience.

Richard Davidson
Via e-mail

That little knot in the stomach is something many of us experience when we think about tackling a high workload environment like Chicago’s. But being able to kick back, smile and remember all the things we did right often makes it all worthwhile.


Math Appeal
A question regarding “The Stabilized Approach” (June 2005): Is the math wrong? The sidebar says to add five knots to the final approach speed, but in the Warrior example is it 73 knots as written or 68?

Daniel C. Stybr
Via e-mail

That’s an editing goof. The text should have read “add 10 knots” and the target airspeed on final approach in the PA-28-161 Warrior should be 73 KIAS. We’ve sentenced one of our editors to work out a series of flight plans with nothing more than a plastic E6-B and a dull pencil.


Got Gas?
I’m always glad to get my copy of Aviation Safety. Each issue gives me either an “Oops, I haven’t thought about that in a while” moment or a “Thanks for the heads-up” reflection. The article “Got Gas?” (July 2005) qualifies, and reminded me of a recent wintertime trip from Manassas, Va., (KHEF) to Manteo, N.C. (KMQI).

On arrival, I refueled that afternoon to reduce the tendency to collect condensation in the tanks in the cool of the overnight. The next afternoon, when I walked toward the plane to pre-flight for the return trip, I noticed a pool of evaporating fuel below the left wing. I didn’t see actual tank leakage, but I saw the plane was on an ever-so-slight slant. That slight slant was the source of the fuel pool.

Over the intervening 24 hours, the fuel in the right tank had formed a hydraulic head against the fuel lines leading to the left tank, forcing fuel out of the left tank vent. My failure to heed the Cessna 172 POH’s admonition to shift the fuel selector to OFF when refueling cost me a couple of gallons of 100LL. Physics is physics. This was a cheap lesson in the long run.

Alan K. Gideon
Via e-mail

Airplanes with a “Both” position on the fuel selector, interconnecting the fuel tanks, are the worst offenders for this problem. Airplanes with little or no wing dihedral can be a problem, also. Put the two design characteristics together and the fuel you carry aloft could be substantially less than you think.

And lest you think high-wing airplanes are the only problem children in the fleet, we routinely see low-wing airplanes with small pools of fuel underneath them, usually caused by midday expansion.


What’s In A Name
I enjoy reading my wife’s copy of your fine publication. She is a student working toward a certificate but we both have the same question: Have you considered including a glossary—or at least a translation—for the abbreviations and acronyms you use?

Case in point: The article on page 2 of the July 2005 issue translates AOPA, which isn’t really necessary. Virtually all the other acronyms are translated. However, on the next page in both e-mails we are left “dangling” with IMC. An oversight, perhaps?

Thank you for your consideration.

Jerry Wing
Knoxville, Tenn.

Point taken. For ill or for good, abbreviations and acronyms are standard operating procedure (SOP) in aviation. We always try to leave the obvious ones alone and decode the rest, but sometimes we manage to foul up beyond all recognition (FUBAR). Oh, and IMC stands for “instrument meterological conditions.” But you probably figured that out by now...


Breaking Glass
While I agree with 99 percent of what the author has to say about technically advanced aircraft (TAA) (“Broken Glass,” June 2005) and the issues raised by failures of the primary and multifunction flight displays (PFDs and MFDs) in equipped aircraft, there is one small issue of error in the sidebar “Are The Backups Enough?” This involves the statement that only Chelton-equipped aircraft have a traditional slip/skid indicator versus an onscreen representation of this instrument.

The Cirrus products have had a mechanical slip/skid indicator (ball) installed at the bottom of the standby attitude indicator since the PFD was introduced. On departure, I often find myself glancing at it more than its electronic counterpart on the PFD. It’s a small mistake but a significant issue of oversight when charged against a particular aircraft model or make.

William Carey
Via e-mail


Ready For Prime Time?
Thanks for the article on options for those of us wanting to ditch our 100LL-burning piston engines (“Are Turbines Safer?” June 2005). While it focused mainly on the emerging market for small turbines, I’m wondering about diesel engine applications for singles and light twins.

For example, diesels have been “just around the corner” for several years now, but still haven’t made much of a U.S. market penetration, although they seem to be growing in popularity in Europe. Why? And, while I’m at it, will they be safer than similar-output piston engines? Thanks.

Mark Stevens
Via e-mail

Diesel engines have the potential to replace gas engines, but we think the jury is still out, at least in the U.S. In Europe, their popularity is definitely growing, driven mainly by the breathtaking price difference between the Jet A fuel they burn and avgas.

The U.S. infrastructure isn’t quite ready for diesels, which is a reason Diamond Aircraft is taking its time to introduce their diesel-powered DA42 Twinstar here. Put it this way—can your A&P reasonably be expected to know how to work on one of these engines without some training or factory support? To us, the lack of supporting infrastructure is a safety issue similar to a thorough preflight inspection.

Like turbines, diesels have the potential to be more reliable. But that potential might lead pilots to fly poorly equipped airplanes when and where they probably shouldn’t.