3WF: GTN FPL sequencing issue resolved

A configuration issue led to the GTN750 not receiving Baro Alt information from the G5, which caused certain DPs with altitude-depending waypoints (e.g. CBAIN, NRVNA) to stop the automatic sequencing of the FPL at those WPs.
One effect was a distracting brief flash of a dialog box offering to unsuspend waypoint sequencing, but absolutely no time to read it, yet alone time to press the button.

That issue should now be resolved – please let Galvin know right away if you still experience an issue of that nature.

Keyless starter in 3WF

Our Cessna now sports a keyless magneto / starter panel:

This ignition switch replaces the outdated rotary key-switch.
By making this change, a couple of things get accomplished:

  • The problem of faulty contacts inside of the key-switch which can cause a hot mag situation is eliminated
  • Operation of the magnetos is returned back to the traditional way aircraft engines are supposed to be operated – starting will be as simple as pushing a button; no more fumbling for the keys
    • Just make sure you have the keys with you in the cockpit after pre-flight so that they’re not inside any of the door locks as you taxi out for a flight.

To start the engine, instead of turning the key you

  1. Turn on both magneto switches (note that the starter will actually work even if the mag switches are off, but the engine won’t fire so that’s just a waste of battery life)
  2. Push the red START button to engage the starter.

During runup, you simply turn off the left mag and run the engine only on the right mag for a few seconds to check on the RPM drop, turn left back on and do the same with the right mag.

When you shut down the engine, instead of turning the key to the left and removing it you need to turn off the two mag switches (don’t press the red START button).

The mag switches should never be left on before or after flight. The MAGS OFF sign provided by Galvin should be displayed in the window when the aircraft is parked and the mags are indeed verified off.

An AFM supplement has been placed in the plane (see plastic box in baggage compartment) and can also be consulted online if there are any questions.

Down the road the magneto-only ignition system may be upgraded to an electronic one (EIS) with basically the same switch panel, but that’s not decided yet.

3WF: New engine doing well

The newly installed zero-time factory-rebuilt engine is doing well and can now be used normally.
The EGT issues are still not fully sorted out, at the moment the #3 cylinder probe is not reporting – that is a minor issue, but it will be looked into with the next service opportunity.

3WF: G5 HSI – to boot, or not to boot…

The most important point first: Normally you shouldn’t press the G5 On/Off switches at all neither for startup, nor for shutdown (when a 3 second shortcut is offered – the rechargeable G5 backup batteries last four hours each, so the extra 42 seconds really won’t make any difference).

The lower G5 (HSI) has occasionally been observed to not boot upon turning on the master switch. If that happens to you, the simple fix is to press and hold the affected G5’s On/Off switch for about ten seconds – just don’t let go – until it boots up.
That’s the only only situation where the On/Off button of the G5 units should be pressed. A recommended fix by Garmin has been applied on Jan 3 to hopefully keep that boot-up issue from occurring in the first place.

3WF: AP circuit breaker

Following Cessna’s initiative on new 172s (cockpit pic) and a US DOT Safety Alert, the autopilot circuit breaker in 3WF now has a yellow plastic ring around it – which does not mean that the AP is INOP.  The purpose of that ring is to locate and pull it faster in the very unlikely case that all standard AP disconnect methods fail, and you need to transfer control of the aircraft from the AP back to yourself:

  • STANDARD: Press the AP DISC (disconnect) button on the pilot yoke left side
    • Alternative 1: press the AP button on the GMC 507 AP mode controller
    • Alternative 2: briefly move both manual electric trim switches simultaneously in either direction
    • If all above three methods should fail to disengage the AP or a runaway trim then by all means pull the AP circuit breaker (that would be a very rare case though), and hand-fly the plane.

Cessna uses a white ring around the AP circuit breaker, but we could only get a yellow one – which is close enough (also note that we deviated from Cessna’s standard of inexplicably marking the fuel pump switch in the same color as the lights – white – whereas we chose blue, just like the color of the 100LL the fuel pump moves before engine startup).

To use the AP please familiarize yourself with the AFMS and this guide published by Garmin – and of course follow the advice of your CFI.