I've been pretty lucky so far (knock on wood). As a student pilot in North Carolina I once experienced a total electrical failure, 10 minutes from my departure airport on a beautiful VFR day. I'm aware of student pilots who have experienced total engine failure - on their first solos - who handled their actual emergency as well as any simulation. Later, I had a transponder fail near Akron, Ohio, which cost me my VFR traffic advisories (and a detour around the Pittsburgh Class B airspace) on a day that was pretty good VFR, even though I was flying in and out of scattered rain showers. And while I was training for my instrument rating, the automatic direction finder (ADF) gave up the ghost - but I didn't shed many tears over that; it spared me from shooting an NDB approach on the checkride (which figured, since I'd finally mastered the things).
Many of you fly airplanes equipped with GPS, which uses satellite signals to determine the aircraft's location. I continue to be amazed by the number of trainers that sport GPS receivers in the panel - many of which also comprise moving-map displays along with the navigation information.
GPS was finding its way into cockpits when I finished my flight training, but the units were primitive by today's standard. No large, full-color moving map - just two lines of text that gave the next waypoint, bearing to the waypoint, your heading, and your groundspeed. My instructor was adamant that we not use it initially, and it remained off during my dual cross-countries - he wanted to make sure that I understood pilotage, dead reckoning, and VOR navigation. He taught me how to use the GPS before my solo cross-countries, however, so that I could use that resource in the panel if I needed it.
At the time, there was a lot of inconsistency among flight instructors when it came to incorporating new technologies like GPS into the flight-training curriculum. Some instructors wouldn't teach GPS usage at all. Many of their students felt that these instructors were dinosaurs, or were intimidated by the technology. It's true that some instructors didn't feel that they understood the operation of these units well enough to teach them - and that situation actually still exists today, with GPS navigation systems increasing so fast in sophistication and complexity that it's hard for instructors to keep up. But a majority of these instructors actually were wrestling with the question of how and when to integrate this new technology into their curricula.
Ignoring new technologies won't make them go away. Actually, instructors who don't ensure that their students are familiar with the operation of a GPS receiver installed in their training aircraft are doing them a disservice. Woe to the students who show up for their private pilot practical test with a GPS in the panel that they don't know how to use - they may be called upon to explain its operation to the examiner.
Some students don't understand why they need to master pilotage, dead reckoning, and VOR navigation. Instructors are obligated to instruct students in aviation's traditional methodologies so that they'll know what to do when the newer technologies fail.
And that failure can come any time. A friend of mine recently flew to North Carolina's Outer Banks. It was a cloudy day with some scattered showers, and he filed an IFR flight plan based on the IFR-approved GPS receiver in the plane. You guessed it - the GPS and accompanying moving-map display went out, leaving him to navigate with one VHF nav radio.
A GPS can cause pilots grief even when it's working perfectly. More than one pilot has punched in the wrong identifier for their intended destination, and then followed the GPS blindly - to the point of fuel exhaustion. Remember that situation awareness begins well before you take off. When your flight-planned destination is 210 miles west of your departure airport, and the GPS display claims that it's 587 miles to the south, that's a strong indication that something's amiss.
Be prepared, understand and use the new technologies available to you in your aircraft - but make sure that you know what to do if one of these high-tech devices decides to fail you.