Although the G1000 is a sophisticated piece of kit, especially when combined with GFC700, one thing I do find limiting is the single HSI/CDI.
In the previous world, say a GNS430 plus a KX155 or two GNS430s, you would normally have an HSI and then a separate CDI somewhere.
So you might have the HSI in GPS mode showing the approach overlay, and the second CDI showing ILS “raw data” so you can cross check. Or vice versa.
With the G1000 you just get a single HSI on the PFD, so either have to select GPS (magenta CDI), or NAV1 (green CDI), but no way to see both at the same time, except for the bearing pointers.
Am I missing something, is there a way to show a second CDI somewhere?
Alternatively is it possible to have a G1000 drive a separate external CDI instrument?
No but if you have a second PFD and unsync them you can have a different CDI on PFD2.
OK thanks, that’s what I thought. A second CDI option on the MFD would be nice.
The second HSI on a second PFD where you have a large MFD in between, can’t be that convenient to look across at?
The G500+GTN setup seems a bit better in this regard.
I never missed that. Except for a non-GPS the approach aid, I always have the GPS on the HSI, and a suitable VOR for cross-check and doomsday on the RMI pointer.
For an ILS – can’t really say I would want a GPS cross-check. If you really want one, use the map display as inset (if you like clutter) or on the MFD (if you like to keep your PFD minimalistic and Zen, as I do)
When I get vectored for an ILS, the HSI immediately goes to the ILS, and I use the moving map to maintain general orientation (so I can see that Thames Radar is vectoring me through the localizer AGAIN).
When I started flying with the G1000 I thought the same. But when I realised that in addition to the CDI (AND and RMI) on one NAV I could have a RMI on the other NAV, then the problem was solved.
ortac wrote:
So you might have the HSI in GPS mode showing the approach overlay, and the second CDI showing ILS “raw data” so you can cross check. Or vice versa.
With a glass cockpit there is a very dangerous failure mode in such situations. The display of the HSI/CDI could freeze. You are established on a procedure and focus on keeping the “needles” in the middle. With a frozen screen, that can cause havoc. I have no knowledge of any incidents but knowing computers and software, I would consider this to be a real danger in a single screen glass cockpit setup.
achimha wrote:
I would consider this to be a real danger in a single screen glass cockpit setup.
But that’s why G1000 (and similar installations) have PFD and MFD where MFD can be switched to backup PFD.
Emir wrote:
But that’s why G1000 (and similar installations) have PFD and MFD where MFD can be switched to backup PFD.
Normally you do not have a CDI/HSI on the MFD. The scenario I described is a “frozen screen” where you believe you are on the centerline. You won’t easily notice.
However: a mechanical HSI/CDI can also have stuck needles. Still, one almost always has more than one HSI/CDI which are completely separate while it is very typical to have just one G1000 screen acting as PFD.
achimha wrote:
Normally you do not have a CDI/HSI on the MFD. The scenario I described is a “frozen screen” where you believe you are on the centerline. You won’t easily notice.
Well, you have altitude on the same screen – you should notice “frozen screen” immediately.
Emir wrote:
Well, you have altitude on the same screen – you should notice “frozen screen” immediately.
There is no reason why the CDI/HSI display wouldn’t be able to freeze on its own. It’s all software and there can be thousands of bugs lurking around.
I feel much more comfortable with a glass cockpit and a second independent CDI or a 2 PFD Garmin setup. I don’t think the G1000 is less reliable than a mechanical CDI but I do not know any IFR aircraft that only has one mechanical CDI. Therefore I think the step from 2 independent CDIs to a single PFD G1000 is not necessarily a step forwards for the “false indication” scenario.
