Zeroing Digital Altimeters

[bqmassey 0]

I'm shopping for a digital altimeter. A thing I've noticed is that some of them claim to constantly be adjusting for field elevation. (I think they sense the takeoff and set that to zero, maybe?)

That's good if you're landing at the same elevation as the runway, but what if you aren't? What if your LZ is not level with your runway?

Do any of the modern digital altimeters have an easy way to zero the alt prior to each jump?

[theonlyski 8]

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I'm shopping for a digital altimeter. I thing I've noticed is that some of them claim to constantly be adjusting for field elevation. (I think they sense the takeoff and set that to zero, maybe?)

That's good if you're landing at the same elevation as the runway, but what if you aren't? What if your LZ is not level with your runway?

Do any of the modern digital altimeters have an easy way to zero the alt prior to each jump?

I know the Neptunes can be adjusted for a DZ offset. Not sure about the others, but I would imagine so.

"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
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[FlyingRadio 0]

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I'm shopping for a digital altimeter.

Most, if not all, manufacturers offer downloadable manuals from their websites. Some even walk through primary features in a 1-2 page document for quicker reading. This should give you an idea of how each unit operates and takes care of functions like zeroing, LZ altitude offset, and all other available features.

Like any skydiving gear, it's important to know your equipment. This means reading the manuals and understanding features, adjustment options, and failure modes.

I jump with an analog on my chest and 2 digitals: a Neptune2 on my wrist and a NeoXs audible in my helmet. Just like you check your analog altimeters before boarding, you check the digitals for zeroing, offset, and alarm settings (if present.)

To highlight the importance of knowing your gear, I have a story from last fall. I was on a plane load where a low-pass at 500' involved tossing pumpkins at a truck in a field. My Neptune2 tracked the slight decline (perhaps several feet per second) at the low-pass altitude as a "jump" and then reset to 0' at 540'. I didn't worry too much about the digital before boarding since I have the 2nd visual altimeter on my chest-strap, although I paid more attention than usual to the altitude readout during the climb. The NeoXs was accurate the whole way.

I relied primarily on my analog that jump for accurate readings, although I was paying attention to the Neptune to see what it would do. The Neptune was very accurate, just low by 540'. In fact, when I touched down after the jump, it read -540 feet.

As I learned later when reading the manual at home, there's a setting on the Neptune2 specifically for low passes like this that tells the unit you're still on a climb so it won't flip to freefall mode early. I didn't have time read the manual before the jump, and I would have manifested on a different load if that was my only visual altimeter, at least until I could pull up the manual for proper operation in such a case.

--
Radio

[Anvilbrother 0]

I zero every altimeter before every jump mechanical and electrical and only takes like 15 seconds.

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[gearless_chris 1]

I had the same thing with my Neptune (and another on the same load did the same exact thing), except it was a flyby for the demo we were doing. Landing at -600 feet makes for an interesting graph. The Neptune 1 has a dz offset also.

"If it wasn't easy stupid people couldn't do it", Duane.

My momma said I could be anything I wanted when I grew up, so I became an a$$hole.

[bqmassey 0]

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I zero every altimeter before every jump mechanical and electrical and only takes like 15 seconds.

Yea, I'd like to be able to do this without the altimeter trying to adjust the zero afterwards. From what I can tell, they will continue to do it until it senses takeoff.