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Finding Non-Precision

As we move forward in time with the proliferation of LPV approaches, the phaseout of non-precision approaches using ground-based navaids such as VOR, NDB, and LOC-only will result in fewer and fewer non-precision approaches. Furthermore, some WAAS navigators often provide an advisory glideslope to non-precision RNAV approaches: LNAV+V and LP+V. The +V refers to the advisory glideslope. An LP (localizer performance) approach is a non-precision RNAV approach that requires WAAS. Bottom line: there is almost always an electronic glideslope lurking in the shadows.

High Too Tech

Step two: Set the clock that held no resemblance to the actual time of day. I fiddled with it for a few minutes and gave up after finding myself seemingly 50 layers deep in menus. I assigned the task to my wife, also an engineer and a pilot. She even got out the manual-a separate one for the man-machine interface but after a frustratingly long time, she was also defeated.

Accidents: AA 1420

One of the last weather-caused airline crashes in the United States was American Airlines Flight 1420 in Little Rock on June 1, 1999. As we mark its 20th anniversary, well tie together some of the radar and thunderstorm skills weve learned in previous articles. Youll also see brand-new radar scans of the storm from modern high-resolution display software-which is far more detailed than that in the NTSB report-and well contemplate what you might see if you encounter a similar storm on modern radar today.

Better than TAF?

A dmittedly, Im an unabashed geek, getting my jollies running statistical tests querying the actual NTSB relational database and publishing my aviation safety research in journals using scientific mumbo-jumbo-the majority (if not all) of which would put any insomniac to sleep in a heartbeat. That said Im also an active general aviation pilot. Here, Ill don both hats as I cover a hot-off-the-press scientific paper published in the Atmosphere journal, translating from highfalutin language into laymans English for the benefit of the general aviation pilot population.

How Far Can You Go?

If issued an en-route clearance limit, you will be given holding instructions. If the pattern is charted, and they rarely are, you might be issued, Hold east as published. Most moving map displays such as the G1000 and GTN series do not show published holds, necessitating a chart, but ATC will issue full holding instructions if requested. The FAA frowns on unpublished holds, saying that only those holding patterns depicted on U.S. government or commercially produced charts which meet FAA requirements should be used. This is another reason why rolling your own at JIDUK, is a shaky idea.

Comparing LPV and ILS

A rriving at your destination on a dreary day, ATC queries you with say approach requested. The landing runway has an ILS and an RNAV (GPS) approach with identical LPV minimums published. Which do you choose? You would be forgiven for thinking, as we initially did, that this is a bit of an inconsequential question. WAAS has enabled satellite guided approaches to have precision comparable to Category I ILS approaches, so what difference does it make? Although true, this doesnt mean that ILS and LPV are identical in all regards.

Hear Back, Read Back

Lets start out with a few simple examples and work our way up. One of the most-used examples is, Tower, Cessna 12345, ready for departure, Runway 14L. Cessna 12345, Tower, hold short Runway 14L. The caution below appears on many charts, but have you really assimilated what its telling you? Its simple. Essentially, if the controller says the word runway you should read back the explicit instruction: Cessna 12345, holding short Runway 14L. This is the proper way to respond.

Our Intermittent GPS Future

Various government agencies think its necessary to potentially render GPS useless throughout hundreds of square miles of the NAS nearly every single day. We who live in the West have experienced this for years. From my home in Santa Fe, NM, I get at least one, sometimes a few, notices of nearby GPS outages every week. But, more recently, those of you in the East have begun to feel more of the same pain.

Just Say It: Unable

ATC will often ask pilots if they can do something somewhat out of the ordinary for the purpose of granting a shortcut or maybe to gain that extra slice of airspace. This subtle word works on both sides of the coin. In the pattern, Tower might ask a pilot to fly a short approach that-if the pilot is unprepared and accepts it-requires a steep and fast dive. Perhaps youve been offered that so they can fit you inside of other traffic, to avoid vectoring you 10 miles out to get behind everyone. Or, perhaps they just need you to cross the approach end of the runway so they can start getting other airplanes out. Regardless, if you dont think you can safely and properly comply, bring on the PIC authority and just say it, Unable.

How Much Is Enough?

Removing the old autopilot will leave holes in the left panel that would be too ugly if we just covered them, so were going to cut new metal. Since were doing that, the shop has suggested we might consider replacing the backup analog airspeed indicator, attitude gyro, and altimeter with an integrated electronic standby instrument. Yeah, thats probably a good idea, especially right now, as the vacuum attitude indicator has been slow to come alive recently and is probably about to die.

Logging vs. Being PIC

You are an instrument-rated private pilot. Your friend is working on the rating and you have acted as her safety pilot while she practices under the hood. Shes doing great. Today ceilings are high but below final approach fix altitudes. You feel comfortable filing IFR as pilot in command while she flies, so you file and off you go in the clubs 172. No hood for your friend today. She does all the flying. Two approaches, with 12 minutes in actual instrument conditions. She did well.

Overlay Approaches

Lets connect some dots. In 1969, NARCO (now defunct) introduced the CLC-60 VORTAC Offset Control Panel that allowed navigation to a phantom fix defined as a distance and direction (rho-theta) from an existing VORTAC. It was touted as the first RNAV system. In the 80s, Bendix/Kings KNS-80 Integrated Navigation System might be considered the first practical RNAV navigator (it had VOR, LOC, DME, RNAV, and GS). Like the CLC-60, it could electronically move a VORTAC and was IFR certified.