Instruments

Like the proverbial bad penny, questions about vertical card compasses seem to resurface about once a year. We suspect owners most frequently consider them during annual when the whiskey model will no longer pass muster or needs fluid or other maintenance.

The vertical card is always an option, but were not sure we can recommend one unconditionally. We recently flew a Mooney with a vertical card and other than some screwy movements when turning to southerly headings, it worked like a charm and we have to say we liked it.

But in talking with other owners of vertical cards, our impression is that results are decidedly mixed. Some owners love them, others rip them out in short order,…

Digital watches have been around since the 1970s, along with digital calculators and even a smattering of digital indicators in cars.

And even though the digital revolution has swept the GA cockpit, steam-driven gauges persist, notably tachometers and manifold pressure gauges. Of the two, the tach lends itself most readily to a digital display.

The tachometer is the primary means of engine control, at least for airplanes with fixed pitch props. Shouldnt it be the most precise and easiest to read? The answer is yes and three companies have digital tachometer offerings that are a cut above that old junker tach that needs periodic replacement or repair.

Horizon Instruments has a…