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3-D instrument approaches

OK so one of the hardest things to do in civilian aviation is the instrument approach.

The FAA lined up a bunch of fixes to each airport in 1970, assigned an altitude to each one, and printed them on paper.

And now, to land at an airport when it’s cloudy, you have to hop-scotch to each fix, being VERY careful to be at exactly the right altitude at each fix.

Too low? You die!

This is made especially difficult because you are having to constantly check the altitude on the paper chart for each fix to be sure that that is what you are hitting on your altimeter… which of course has no idea at all what sort of altitude you are supposed to be at at any given moment. Compounding this miserable lack of communication between chart and instrumentation is that the minimum altitudes are shown for each FIX, but, umm… we fly an airplane BETWEEN fixes! Then along came all the great EFB Apps like Xavion and Foreflight, which presented the instrument approaches for you as…. as perfect replicas of the stupid old paper maps.


For altitude, there was no actual benefit beyond having a old paper approach plate in your lap when using Xavion or Foreflight when flying an instrument approach, because you still had to go back and forth between the image of the 2-d map and the altimeter, trying to be sure you were at the right altitude at every moment. And one slip should technically mean death.

What a ridiculous disaster…. and that is assuming you already have a G1000 or some other high-power GPS-driven map!

No wonder we have to take an instrument refresher course EVERY SIX MONTHS to be allowed to fly IFR! The system makes no sense to use! Of COURSE nobody could remember it all!

So now, Xavion knows the instrument approaches, in 3-D, and plots them as hoops to fly through, with the altitude properly set for the approach! Now, no more trying to cross-reference between your approach plate and flight instruments: The hoops in Xavion are 3-D, giving you location and altitude for the entire approach without having to constantly look away from your flight instruments to try to study an approach plate!

Here is how it works:

In Xavion, simply enter your destination in the NAV screen. If your destination is an airport, then every approach to that airport will pop up right below the airport, complete with each initial approach fix for each approach. 

Just choose the one you want.

Bang. 3-D hoops are splatted down from your location to the initial approach fix, through all the fixes of the approach, right down to touch-down. Their altitude is of course automatically set for the correct altitude for each bit of the approach, complete with 3-degree descents starting when needed based on your current altitude. Just fly the hoops all the way down. Done. No altitude to set, ever. Got to the MDA or DH and don’t see the airport? OK just hit the MISS button in Xavion and the hoops pop to the missed approach procedure, all the way through the entry to the holding pattern at the end!

So now, finally, we have instrument approaches where you just select the approach and fly the hoops in 3-D! I find it much easier to use than my Garmin, which does not automatically set all the altitudes (you have to enter initial altitudes manually, and any manual altitude past the IAF messes up the whole approach). Now having flown these instrument approaches in Xavion, I can’t imagine trying to muddle through an instrument landing any other way! Xavion is on the App Store now, with this update to it just approved today, and you have to buy the Seattle Avionics data subscription to get all this cool stuff!

So now the two hardest maneuvers in civilian flight, the engine out landing and instrument approach, are shown in Xavion as hoops to simply fly through! Cool!