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One of the nicest things to know on a nonprecision approach is your distance from the Final Approach Fix and, subsequently, how far you are from the airport itself. With RNAV equipment, the distance ques- tion is answered with considerable accuracy; you can put a waypoint on the FAF, another on the airport, and even if course guidance must officially be obtained from another source, accurate range informa- tion is a great help. (You can use RNAV steering information to back up the primary navaid, but unless it’s a published RNAV procedure, that’s the best you can do.) This is especially true in the case of an on-airport radio aid, which previously required an extension of the time outbound and occasionally a “plunge” after the final approach 134

Fig. 10-2 Typical GPS approach procedure chart. (Copyright Jeppesen Sanderson Inc.; not to be used for navigation; all rights reserved)

Chapter Ten

fix to guarantee reaching MDA prior to reaching the airfield; with an RNAV distance display working for you, all the guesswork is gone.

There’s not a pilot flying today who wouldn’t agree that always having an alternate airport in mind — at any point on any trip — is a good idea. The assurance of someplace to go if things start to go bad is especially important at night, in weather, or both. Enroute with RNAV, you can keep inactive waypoints programmed for “instant al- ternates” throughout the flight; it takes a little extra preflight planning, but being able to push a button in time of need and have an accurate course and distance to a safe haven come up on the cockpit display is luxury. Upgrade that to sheer luxury when you have a contemporary Loran or GPS in the panel because these units are preprogrammed with nearly all the airports in the country, and they display the nearest airport information automatically.

Holding at an airway intersection or an NDB is a piece of cake with RNAV. Instead of navigating on one radial while watching for the other to center, figuring out what the DME reading should be, or tying yourself in navigational knots trying to kill wind drift over an NDB, you can put a waypoint on the holding fix and fly on the proper radial until FROM appears; area navigation makes every hold- ing fix a VOR.

Or how about this one? You’re inbound to a busy terminal, visi- bility barely 3 miles in summer haze, and you are asked to report on a 3-mile final. Up until now, that position report has been little more than a good guess — especially at a strange airport — but with a way- point on the airport, you can line up on a genuine final approach (set the OBS to the runway heading and keep the needle centered) and let the controller know when you’re exactly 3 miles out; that’s a big help for everybody concerned. And if you want to show off a little, get superaccurate — tell the tower that you’re “3.1 miles on final.”

Summary

Most nonprofessional instrument pilots can probably be categorized as those who fly only short IFR trips close to home for currency or practice, or those who use their ratings for frequent, relatively long IFR flights. The former group might as well save the money they’d spend for RNAV equipment — at least until the plug is pulled on the VOR system — because there’s lots of quality instrument time to be logged using the federal airways and VOR approaches. But IFR “fre- quent flyers” should give serious consideration to equipping their air- planes with Loran or GPS because of the significant benefits these 136

black boxes provide. (If you’re flying with a good Loran set, hang on to it. Not only will it serve you well until the government phases out the system, but by the time you are forced to make the switch to GPS, the technology will have improved remarkably. The price will likely be lower as well.)

There’s a lot of navigational information available from even the most unsophisticated Loran installation, and when it comes to GPS, well, the stuff you can bring up on the screen is truly mind-boggling. As you become familiar and facile with long-range equipment, you’ll find more ways to use that information to improve the flexibility and efficiency of your IFR operations.

But perhaps the most significant advantage for Loran and GPS users who fly frequently and far is the ability to simplify their flight planning and their inflight navigational chores by filing and flying

direct. It was mentioned earlier in this chapter, but based on personal

experience, you should file RNAV direct from airport to airport at every opportunity — quite literally, every flight. You’ll find that your request will be turned down only on rare occasion, and even when that happens, it’s highly probable that you can pick up a clearance direct to your destination at some point along the route. For the Loran/GPS crowd, the VOR system exists as a backup to both enroute and terminal IFR navigation.

We’re in the midst of a near explosion of avionics technology, and this time, small airplanes are not being shut out. It’s a lot like the need to get on the information superhighway if you’re going to re- main competitive in whatever you do — including flying IFR — so you should equip yourself and your airplane accordingly for the future.

11

Enroute Procedures