Menu Sign In Contact FAQ
Banner
Welcome to our forums

Is IFR with a single GPS (or single radio) legal?

From the FAA AFM supplement for a KLN94 GPS (in this case for the C172/182 series as I don’t have a version for a TB20 to hand)):
SECTION 2 – LIMITATIONS
6. The aircraft must have other approved navigation equipment
appropriate to the route of flight installed and operational

@wigglyamp in my KLN94 AFMS, US FSDO approved, detailed here I can find the bit about alternative equipment being available too

It looks like a standard phrase.

A G500 is a dual screen device which most people set up to include an MFD

Sure, but a G500 is an “MFD” with some other bits. The GPS is separate. Also this is a “40k+ installation”. You could do 2×GTN750 or 2×IFD540 (if you can find two which work 100%) inside that figure.

Administrator
Shoreham EGKA, United Kingdom

From here

Peter wrote:

No relevance to GA though, especially in Europe where NAV (ILS etc) is needed.

NAV is needed, but not necessarily in the same box as the GPS. If you have a GPS/NAV/COM, like the GTN650, then in practise you need a second box with either NAV or GPS to satisfy requirements that you must be able to safely conclude an IFR flight in case of failure of any one box. If the cloud base was high, one could argue that radar vectors would be enough so that the second box was COM only, but I wouldn’t be comfortable with that.

On the other hand one GPS box and one NAV/COM box would work.

Last Edited by Airborne_Again at 09 Nov 12:03
ESKC (Uppsala/Sundbro), Sweden

What is this requirement? My aircraft is IFR certified, but only has the one 430 gps/nav/com.

Off_Field wrote:

What is this requirement? My aircraft is IFR certified, but only has the one 430 gps/nav/com.

There is no such thing as “IFR certification”. (At least not for EASA aircraft.) The type certificate for the aircraft type may limit operations to VFR, but if it doesn’t then all you need for IFR is the proper equipment according to part-NCO.

The relevant paragraph for this discussion is NCO.IDE.A.195, item (b).

NCO.IDE.A.195 Navigation equipment
(a) Aeroplanes operated over routes that cannot be navigated by reference to visual landmarks shall be equipped with any navigation equipment necessary to enable them to proceed in accordance with:
  (1) the ATS flight plan; if applicable; and
  (2) the applicable airspace requirements.
(b) Aeroplanes shall have sufficient navigation equipment to ensure that, in the event of the failure of one item of equipment at any stage of the flight, the remaining equipment shall allow safe navigation in accordance with (a), or an appropriate contingency action, to be completed safely.

The key phrase here is “or an appropriate contingency action”, so you don’t have to duplicate your nav equipment.

Last Edited by Airborne_Again at 09 Nov 13:28
ESKC (Uppsala/Sundbro), Sweden

Very interesting, thanks AA. Yes that does appear to cover the get out.

Off_Field wrote:

Very interesting, thanks AA. Yes that does appear to cover the get out.

I could perhaps have been more clear. While you don’t have to duplicate, you do need some nav functions split over different boxes. So if all you have is a single GNS430, then it’s not ok for IFR unless weather conditions are such that you can revert to visual navigation at any time.

ESKC (Uppsala/Sundbro), Sweden

That means anybody with a single navigator box cannot legally fly IFR.

“or an appropriate contingency action, to be completed safely.” should include ATC vectors, so you need a separate VHF COM radio, but not a separate means of navigation.

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

That means anybody with a single navigator box cannot legally fly IFR.

“or an appropriate contingency action, to be completed safely.” should include ATC vectors, so you need a separate VHF COM radio, but not a separate means of navigation.

It might be stretching it as a VHF COM is not navigation equipment. But I agree that would be a defensible position if there was a PAR or SRE approach handy or the cloudbase was above the MSA.

ESKC (Uppsala/Sundbro), Sweden

I’ve merged a couple of threads on the same topic.

It’s quite interesting, and not unrelated to the other very old debate regarding a dual GNS installation, which EASA refused to certify (maybe still does?) because they said both could fail concurrently, and the STC which one UK avionics shop produced to get around this required a separate radio. One thread is around here and that got blamed on some FAA rule which nobody in the US interprets that way

Administrator
Shoreham EGKA, United Kingdom

Airborne_Again wrote:

But I agree that would be a defensible position if there was a PAR or SRE approach handy or the cloudbase was above the MSA.

It’s not only on the approach – but you need to be at least RNP-5 to legally fly IFR in most parts of European airspace system. And a Com-Radio can hardly be claimed as RNP-5 …

Also if we apply common sense: What the regulator intended to ask for is that no failure of a single piece of equipment should constitute an emergency. Lack of own means of navigation and being dependent on radar vectors from ATC is an emergency.

Therefore one might argue that IFR in VMC is legal with just one navigator, IFR in IMC is pretty clearly not!

Airborne_Again wrote:

There is no such thing as “IFR certification”. (At least not for EASA aircraft.)

This statement could be misleading: There are obviously types where the type certificate and/or the certified POH says “VFR (day) only”. And in those planes IFR flight is obviously not allowed even if the equipment would be sufficient.

Last Edited by Malibuflyer at 10 Nov 11:00
Germany
Sign in to add your message

Back to Top