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October 17 Review of Jeppesen VFR+GPS ChartsJeppesen is gradually releasing a series of new VFR+GPS paper charts that, according to the company, "offer a fresh perspective on what a VFR chart should be with intuitive symbols and colors, better coverage areas and an emphasis on GPS navigation."
October 13 Review of CH Products Eclipse YokeCH Products has updated its line of flight yokes with the Eclipse, an all-in-one yoke that includes an innovative solution to the "rudder problem" and several new features that put scores of customizable controls at your fingertips.
My review of the Eclipse is in the Product Reviews section of www.BruceAir.com. October 05 “Fly Visual” Segments on LPV and LNAV/VNAV ApproachesThe FAA is publishing hundreds of new RNAV approaches each year, and the agency has emphasized the production of WAAS-based procedures with LPV (localizer performance with vertical guidance) and LNAV/VNAV minimums. Indeed, as of August 27, 2009, in the U.S. there were 1,820 approaches with LPV minimums versus 1,318 category I ILS procedures. These approaches, like conventional precision approaches, have minimums set at a DA (decision altitude). For several reasons, procedures with LPV and LNAV/VNAV minimums are classified as “semi-precision” approaches (technically, they are APVs—approaches with vertical guidance), but to a pilot, they are (usually) functionally the fraternal twins of an ILS. To fly to an RNAV approach with LPV or LNAV/VNAV minimums, you track a course like a localizer and then intercept and descend along a glide path that, in the cockpit, looks like the glideslope on an ILS. You continue the descent on that glide path until you reach the DA published for that approach. For example, here are the minimums sections for a typical ILS approach and for the RNAV (LPV and LNAV/VNANV) procedure to the same runway (at KALW): These charts illustrate the principle of a DA. By definition, at the DA, you must begin a missed approach if the requirements set out in 14 CFR Part 91.175 aren’t met. Many books, including FAA training handbooks, emphasize that, after you reach the DA, you can’t continue flying along toward the airport as if the DA were an MDA (minimum descent altitude) defined for a non-precision approach (i.e., a procedure without a defined descent path and that provides only lateral guidance). But exceptions (albeit poorly explained at present) exist. Consider the RNAV (GPS) RWY 32 approach at Reno/Stead (KRTS). It includes a “fly visual” segment from the DA to the threshold—a charted distance of 4.1 nm if you fly to the LPV minimums. But the visibility requirement for the LPV minimums is 2 miles. In other words, at the DA, if you have 2 miles visibility, you can continue flying toward the runway until you see the approach lights, the runway, etc. You aren’t required to begin a missed approach at the DA as you would on a conventional precision approach. Here’s another example—the RNAV RWY 24 approach at KHQM: The minimums section for procedure above includes separate “fly visual” notes for the LPV and LNAV/VNAV minimums. You can find similar notes on RNAV approaches at many airports, especially those, like KHLN, set amid mountains. The instructions on these charts are superficially clear. When you reach the DA—even if you don’t see the approach lights, runway, or other cues required by 14 CFR Part 91.175—you can “fly visual” a specified distance to the runway and land—provided you have the flight visibility specified in the minimums section for that approach. But the instructions leave many questions unanswered. For example, can you continue flying along the glide path, or must you remain at the DA, maintaining it as if it were an MDA, until you see the runway environment? Must you fly the specified course to the runway? What if you don’t pick up the lights or the runway and begin a missed approach after you descend below the DA (i.e., fly past the point where the final approach course and DA intersect)? Are you protected from obstacles until you’re established on the charted MAP? And what about 14 CFR Part 91.175? Doesn’t flying past (and/or below) the DA without the required visual references violate the regulations? As I noted at the beginning of this post, specific guidance on these issues has been hard to come by. The August 27, 2009 update to the the AIM includes the following language in section 5-4-9 g. Visual Segment of a Published Instrument Approach Procedure:
Additional clarification, including updated language in the Instrument Procedure Handbook and updated chart formats (perhaps including separate approach plates for APVs and LNAV-only procedures), may be forthcoming, however. With the help of Bruce McGray of the FAA, I have found guidance from AFS-400/420, the Flight Technologies & Procedures Division—Flight Procedure Standards Branch of the FAA. Here are the highlights (links to references follow): When continuing along a “fly visual” segment of an IAP:
References:
October 02 Stalls, Incipient Spins, and Inverted FlightI just posted a couple of videos on YouTube that show a typical first flight for one of my stall/spin/upset students and an introduction to inverted flight and recovery from inverted flight. The pilots on these flights are typical GA flyers. Neither had previous experience with spins, aerobatics, or unusual attitudes beyond those practiced in private pilot training. They usually fly Cessnas and Pipers. Their initial reactions are typical. They both find the experience initially disorienting, even though we've completed an extensive ground briefing that includes videos like these. Like most folks I've flown with, they react slowly and hesitantly because they're in new situations. I was no different when I began flying aerobatics. That's why I focus on a variety of stalls and incipient spins and build up to developed spins--and why I include basic aerobatics in the syllabus. That progression gives folks opportunities to experience a wide range of unusual attitudes, become accustomed to Gs (we try to keep loads within the normal category limits), visualize the lift vector, and reinforce the idea that angle of attack, not pitch attitude relative to the horizon, is the critical concept. |
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