Altitude reminder?

BigBadLou

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Lou
I searched but did not find a thread on this topic so forgive me if this has already been discussed under a different name.

What I would like to ask about is a GA device that works just like the real thing in bigger and faster aircraft. We all know altitude reminders and how useful they are with their ding for "1000 to go".
For us GA guys, there is no such thing (at least to my knowledge). Or is there?

I realize that smart phones can do that via apps based on GPS altitude. But that is not the same as barometric altitude. So you cannot rely on its accuracy, nor should you. It can be hundreds of feet off.
GPS units could do that too, if they have a baro input and are programmed so. Not all of them offer this functionality.
Glass panels should offer it by default (and if they don't, the manufacturer should be lynched).
But for regular six-pack cockpits, the options are none, it seems.

I checked on some aviation websites and did not find any simple handheld useful devices to fulfill this reminder function. I did find expensive altitude alarms for many AMUs.

Do y'all know of a simple altitude reminder device that will chime/alarm before reaching preset target barometric altitude?
 
Don't do much IFR in GA these days, but when I do, I have a small pad of paper out to write clearances, altitude assignments, and so on.
 
1. I realize that smart phones can do that via apps based on GPS altitude. But that is not the same as barometric altitude. So you cannot rely on its accuracy, nor should you. It can be hundreds of feet off.

2. GPS units could do that too, if they have a baro input and are programmed so. Not all of them offer this functionality.

3. Glass panels should offer it by default (and if they don't, the manufacturer should be lynched).

4. I checked on some aviation websites and did not find any simple handheld useful devices to fulfill this reminder function. I did find expensive altitude alarms for many AMUs.

1. Where did you find that GPS altitude can be hundreds of feet off from barometric altitude? In my experience they differ by dozens of feet max.

2. Why would the GPS unit have to have barometric input when the GPS altitude is more accurate?

3. Why would you lynch a manufacturer for not designing in something that nobody seems to want?

4. A simple barometric pressure sensor from any of the pop electronics sites (Adafruit, etc.) and a versatile microprocessor could be built for less than $50 in parts and sell for a couple of hundred. However, convince me that I'd sell a thousand units in ten years. Don't see a lot of people yipping up the tree for this product.

Jim
 
1. Where did you find that GPS altitude can be hundreds of feet off from barometric altitude? In my experience they differ by dozens of feet max.

2. Why would the GPS unit have to have barometric input when the GPS altitude is more accurate?

3. Why would you lynch a manufacturer for not designing in something that nobody seems to want?

4. A simple barometric pressure sensor from any of the pop electronics sites (Adafruit, etc.) and a versatile microprocessor could be built for less than $50 in parts and sell for a couple of hundred. However, convince me that I'd sell a thousand units in ten years. Don't see a lot of people yipping up the tree for this product.

Jim
I've had my GPS altitude and altimeter off by 100-200 hundred feet before too. But I think we often think barometric altitude to be actual MSL when it isn't adjusted for temperature and can be off by a bit.
 
Think my 330 transponder has something like that, never found the need though

Closest I use is a radar altimeter DA/H alerter on larger aircraft, but that's only to back up my normal altimeter and I just brief the DA before the approach, no alerter
 
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Alot of the current crop of phones have baro sensors in them now (my iPhone 6 does). All someone needs is an app to allow you to put in the altimeter setting and the cleared altitude and you'd have it. Surprised ForeFlight hasn't already done it.
 
I have an Apollo Alti Track in my Venture that does pretty much what you ask. It takes some manual inputs before each flight but it alerts me at pre determined altitudes for several scenarios.
 
I use a low tech "pointer on a suction cup" solution....

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And Lou, check in with qbynewbie on the Red board for his DYI solution.
 
1. Where did you find that GPS altitude can be hundreds of feet off from barometric altitude? In my experience they differ by dozens of feet max.

2. Why would the GPS unit have to have barometric input when the
1. Where did you find that GPS altitude can be hundreds of feet off from barometric altitude? In my experience they differ by dozens of feet max.

2. Why would the GPS unit have to have barometric input when the GPS altitude is more accurate?

3. Why would you lynch a manufacturer for not designing in something that nobody seems to want?

4. A simple barometric pressure sensor from any of the pop electronics sites (Adafruit, etc.) and a versatile microprocessor could be built for less than $50 in parts and sell for a couple of hundred. However, convince me that I'd sell a thousand units in ten years. Don't see a lot of people yipping up the tree for this product.

Jim


3. Why would you lynch a manufacturer for not designing in something that nobody seems to want?

4. A simple barometric pressure sensor from any of the pop electronics sites (Adafruit, etc.) and a versatile microprocessor could be built for less than $50 in parts and sell for a couple of hundred. However, convince me that I'd sell a thousand units in ten years. Don't see a lot of people yipping up the tree for this product.

Jim

AIM 1-1-17 " Do not use the GPS derived altitude due to the large GPS vertical errors that will make the integrity monitoring function invalid."
 
Is the AIM regulatory?

Where have I heard that before? A specious argument at best. Given the full title: " Aeronautical Information Manual (AIM) Basic Flight Information and ATC Procedures," an administrative law judge might very well give it the benefit of the doubt. No one is going to get a violation for using GPS altitude, but if doing so were ever a cause for investigation the wording in the AIM would play a part in assessing the pilot's attitude with regard to following instructions.
 
I have a KFC150 autopilot with altitude preselect in my Mooney. I can set the desired altitude and let the autopilot get me there or hand fly it. Regardless it will ding when within 1000 ft either way, going up or down.
 
Cirrus does a single chime within 1000ft of the pre-selected altitude. It will also say "altitude" when +/- 200ft of the pre-selected altitude and the pre-selected altitude turns amber instead of blue. It also makes a minimums call and a 500ft call. When I'm flying a Cessna or Piper without these call outs, I'll usually just write the altitude down and circle it
 
In the trivial info category is that an enunciated altitude alert can be added to an Aspen PFD fairly easily. Also the Garmin 330es will alert when leaving an altitude if it is connected to the audio panel and ya want it to do so.
 
For us GA guys, there is no such thing (at least to my knowledge). Or is there?

Do y'all know of a simple altitude reminder device that will chime/alarm before reaching preset target barometric altitude?

Electronics International ASC-5A Superclock, many newer transponders do it, Shadin AMS 2000 Altitude Management System, Some digital altimeters, Icarus AltAlert, the list goes on.

The Garmin G5 has a settable altitude bug but no audio warning

Dynon D10A and D100 appear to have audio line out to an audio panel and altitude bug.
 
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The 2-axis version of the King KAP140 will serve as an altitude alerter when the autopilot is off, I found it annoying and usually set it to some ridiculous altitude. Then again I was mainly instructing in it without much straight-and-level time.

What I would like to ask about is a GA device that works just like the real thing in bigger and faster aircraft. We all know altitude reminders and how useful they are with their ding for "1000 to go".
For us GA guys, there is no such thing (at least to my knowledge). Or is there?

Pretty sure there have been portable devices on the market for this in the past, but maybe not now. Probably not popular enough.
 
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