KLN94 GPS and flying "overlay" GPS approaches

On 06/14/06 12:49, Peter wrote:
Mark Hansen wrote

Now, if your unit follows the same rules, and none of your approaches have
"gps" next to them, then what good is the fact that the unit is certified
for IFR Approaches?

Something must be missing...

The bit that's missing is that I am not in the USA

Well ... I wasn't missing that part ;-\


There are some proper GPS approaches in Europe that are fully active
now, e.g. LKPR

http://www.ead.eurocontrol.int/eadba...2006-04-13.pdf

but only a few of them. All the rest of the approaches in the European
GPS database are overlays, and I don't think they are authorised for
"GPS".

In the U.S., GPS Overlay approaches can be flown by an IFR-certified
GPS unit (TSO C-129 and the 146 whatever one).



My KLN94 manual is the same as yours - the GPS is identical too.

Good question about what is IFR certification good for over here. One
does need BRNAV capability at FL095+ in Europe and in the GA context
that means GPS, and it has to be a TSO-129 unit. But a lot of IFR GPS
installations have the GPS set to VFR only as a certification
requirement (mine was) and that works for en route nav.

Do you know whether or not you're allowed to use the GPS as primary
navigation to fly the GPS overlay approaches in your country?


What puzzles me is whether the KLN94 actually fails to do anything
with the HSI, when on a non-"GPS" approach. That sounds almost too
"vindictive"

Well, if the GPS cannot switch to Approach (Active) mode, then it
will still drive the CDI, but not at 0.3sm sensitivity. The manual
states that it will remain at the 1.0sm sensitivity.

I was taught that you cannot legally fly the approach with the GPS
unless it switches to Approach (Active) mode. Maybe that's a U.S.
only rule (I doubt it).



--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA