Radar, I guess. Though if you have lost PFD and MFD, I don’t know if you could tune the radio to get radar service – you’d have to depend on whichever frequency you were last on, maybe an argument for always having 121.5 tuned in on box 2.
I actually think the most common failure mode would be a PFD failing which means you do it on the other PFD. I find it hard to think how you could lose both PFDs and still have a radio.
Timothy, you need to pull a few CBs to kill both screens.
Initial IR tests (UK). The current expectation is that pilots need to demonstrate a hold and at least one of the two approaches using raw data; you can be asked to complete a GNSS procedure for your non-precision approach. For the rest of the flight you can use what you want, correctly.
A/P is allowed for en-route phases as long as the A/P is not in NAV mode (i.e. you need to slave it to the hdg bug).
A trivial job, like displaying NAV1 and NAV2 on two CDI’s (possible with any IFR conventional cockpit), is not possible on the G1000.
But you can always show two (or three) needles on one HSI-like instrument.
A/P is allowed for en-route phases as long as the A/P is not in NAV mode (i.e. you need to slave it to the hdg bug).
Why? Seems an odd requirement.
I find it hard to think how you could lose both PFDs and still have a radio.
How about a software bug? I would assume that both PFD’s run the same software, so if there’s an input condition that causes the PFD to crash, then both would be affected, but not necessarily the radio..
…yes, but if the screens have frozen or died, how would you tune the radios?
That is the problem. If you lose both screens, you are in potential trouble. There are obviously redundant power buses, AHRS, ADCs, Pitots etc but. If all that goes I shall fly with my iPad and GDL39-3D and make an approach with that.
Of course the MFD would also need to fail as the PFDs can revert to the MFD
How about a software bug?
Certainly possible. I have seen many PDFs and probably even some (corrupted) Jpegs which crash the rendering software.
If I had a G1000 aircraft I would be tempted to install one little radio somewhere, corrected directly to the battery (via a switch and a CB) for
you need to slave it to the hdg bug
I didn’t have that in 2012. I flew a part of the track in NAV mode, and even remember discussing (what would effectively be) roll steering with the examiner.
Peter there is an emergency bus/switch which powers the PFD1 and COM1 plus a few other things.
And of course I carry a handheld.
