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Having an issue with my altimeter. The kollsman window has always been hard to read in the daytime unless the instrument internal lighting is at full bright - but last flight I actually had to turn the plane so that the sun was not on the face of the altimeter in order to read the kollsman. Makes me wonder if the internal illumination is dimming over time. This is the original model number altimeter that was used in the founders edition - although it has been replaced four times under warranty. Anybody else have this issues?

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There are numerous issues with the altimeters. My LED readouts are weak and have dead spots. The altimeter jambs between 950 and 50. I have had to resort to using my iPad with ForeFlight to get altitudes in the pattern. Icon is saying they are looking for a better supplier but that, at this point, no supply has been assured. To make matters worse, even if we wanted a less-than-great replacement while we wait for a good altimeter, they are in short supply and Icon needs them for production... No good news. I am going to stick-it-out with the limping altimeter until good quality ones are available... More to follow.

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We have SN88, founders addition. In the last year we have experienced the same thing. I just picked up the plane from annual and the Baro is impossible to read now — even when the sun hits it just right, it appears to be stuck reading 30.15. I share your frustration for sure

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I own SN 00060 and have had the same issue with the Kohlsman window in the altimeter being unreadable, for about a year. Customer Support explains that they are working the issue against supply chain headwinds. Not a safety issue, as the Trig TT22 transponder gets its altitude from ADS-B OUT sending GPS elevation, so ATC has an accurate bead on altitude. I ask them from time to time what they are showing and adjust the altimeter reading based on their feedback. During water-flying I keep the altimeter set to zero on the water. In the pattern away from the water, the GPS elevation from my watch, iPhone, or iPad provides backup.

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I think we are on our third altimeter, maybe fourth even? The one we have now was used because there were no more and the manufacturer was "moving" and strangely couldn't seem to find anything...which was really I think just a foreshadowing of them going out of business.

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Part of the challenge facing ICON is that the altimeter is "coarse," showing 1,000 feet for one rotation of the large needle. While I am a fan of the dial for the A5, not many aircraft use this kind of display of altitude. So finding a supplier willing to go through FAA TSO authorization and then building a production line is tricky. I would like to see an altimeter with a dial like in the A5, driven by GPS (except when GPS goes down).

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Bruce, suppliers don’t need to meet any certification or TSO for instruments in a Light Sport Aircraft. Matter of fact the current altimeter and airspeed are not TSO’d. I think the bigger issue is the NRE in developing one with a small market. I’m not sure I get your comment altimeter being “coarse”. The current altimeter is actually more finely marked in 10ft increments than typical altimeters with are 20 ft increments. The difference is that its single needle is indicating the increments small increments within the 1,000 ft and the digital displays show every thousand ft plus 100 ft increments. That said I think you all have had at this point an altimeter replaced, the display reliability and the needles getting caught on the display face happen a lot. The very original altimeter that came on the first 20 aircraft was a single needle with only 100ft increments. I would not buy an altimeter that was GPS based. GPS altitude is different and has much more error than barometric. Even with WAAS. Positionally GPS with RTK can be down to centimeter accuracy but the altitude is not that accurate. A sensitive and appropriately designed sensor using barometrics electronic or bellows based can be and are extremely accurate.

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A follow up on this. I discovered that the original company that makes the altimeter did in fact go out of business. Another company bought the defunct company and continued production of the altimeter. There should be a shipment of altimeters to Vacaville in 3 weeks but they are allocating a certain number to A5's in production as there is a back log. Also, they need to be bench tested and flight test inspected before being returned for service. So, expect quite a delay in getting a new altimeter if you need one.

I agree that the transponder does fine at giving the gps altitude and it's easy to verify altitude with ATC if needed or entering controlled airspace.

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Another company bought the defunct company and continued production of the altimeter. There should be a shipment of altimeters to Vacaville in 3 weeks but they are allocating a certain number to A5's in production as there is a back log. Also, they need to be bench tested and flight test inspected before being returned for service. So, expect quite a delay in getting a new altimeter if you need one.

Well I still have the last one that's supposed to have been warranty replaced sitting in the box to send, that's a positive direction at least.

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A follow up on this. I discovered that the original company that makes the altimeter did in fact go out of business. Another company bought the defunct company and continued production of the altimeter. There should be a shipment of altimeters to Vacaville in 3 weeks but they are allocating a certain number to A5's in production as there is a back log. Also, they need to be bench tested and flight test inspected before being returned for service. So, expect quite a delay in getting a new altimeter if you need one.

I agree that the transponder does fine at giving the gps altitude and it's easy to verify altitude with ATC if needed or entering controlled airspace.

As for the transponder and altitude: The transponder measures PRESSURE ALTITUDE from the static source on the aircraft which is measured at the tail (hole at the center of the Half moons on either side of the tail) This is not GPS altitude and is not MSL altitude either. Pressure altitude is the altitude you will read with the Kollsman Window set at 29.92. ATC does a correction on this data once received but all transponders and encoders transmit Pressure Altitude.

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Bret, in an unrelated topic to the Icon and its altimeter, I want to dive into the rabbitt hole here for minute with you. You stated above, and others concur, GPS altitude (even with WAAS) has much more error than baro. When I shoot an LPV approach, is not the glide-slop indicator derived from GPS altitude, or does my Garmin GTN 750 use my baro altimeter to calculate the Glide Path?

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Yes the Glide slope is based on GPS altitude for your LPV approach but for the most part the Decision Altitude of the ILS is slightly better sometime not depending on the ILS install. GPS also requires RAIM and have WAAS from being out. For the most part GPS is pretty accurate but far less accurate and easily diluted by signal where as barometric if properly designed in the electronic form is quite accurate and very reliable. To this day we still never do any flight test using GPS altitude almost all testing is done using barometric. I once did airspeed calibration in a T-38C using a theodolite (precision radar tracking) to measure the geometric height of the aircraft and also used this measure to calibrate the installation in the aircraft. My biggest problem with GPS is the consistency and understanding where the errors come in at any given time in the same airmass. Barometric is well understood and fairly uniform for most all aircraft. The testing requirements are established and if you are on a IFR certification you have to pass a Pitot / Static test every 24 Calendar Months.

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James Andrews informed me that NEW altimeters are now flowing at Icon Mexico. Some extras will be available as spares/replacements. I would love to hear from anyone getting a replacement if the new ones are behaving as expected/desired. Please post on this site if you have info! Thanks.

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The picture below was sent to me by Mandy Chung - new vs old altimeter. As you can tell the new altimeter does not give any precision. Zero to one is 100 ft on the old altimeter but it is 1000 ft on the new altimeter.

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And at 11,000'?

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I guess they figured we don't need to know anything above 10,000 ft - tooo scary!

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Whoa wait a second…The altimeter in the left is the very very old UMA made single needle altimeter ASN 00001 through 00020 were produced with those. The one on the right is the icon designed all digital altimeter. It has OLED screens and the needle can get get stuck when the back face isn’t installed well. The one on the right has higher precision than even most altimeters on aircraft with 10 ft increments. Most altimeters are 20ft increments and two needles.

michael did I read that correctly that you’re saying icon is switching back to the old not sensitive altimeters? Those were not good either. I suppose it’s better than one that doesn’t work at all (shrug shoulders). The new digital ones were not great but still way better than the old mechanical ones shown on the left photo.

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Mandy told me there would be 20 of the UMA altimeters (on the left) available end of June - July. She indicated there was a shortage and that was all that would be available for now.7costcost- cosA (MFG: UMA)
INDICATOR, ALTIMETER, SUBASSY, *SERIALIZED*
COST: $1918.86/EA
Estimated Availability: End of June-July 2023

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BTW - cost is $1918.86

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Sheesh I guess it’s a stop gap measure to make them available in the interim.

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I’ll pass and wait. Foreflight will have to do.

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I noticed that in the latest revision of Foreflight you can access the baro-altitude of a Sentry or Stratus ADS-B receiver and display the baro-altitude based on the nearest ADS-B reported altimeter setting. THIS seems like a great work around for the ever-failing altimeters in the A5.

Unfortunately I use a Garmin GDL-52 - which apparently Foreflight won't access for baro-altitude.

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GPS Altitudes from the 796 and iPad will have to do until we get a functional altimeter. other than the scraping and snapping that happens at the 12 O'clock, it eventually catches up after 5-8 seconds of lag.

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I disagree Michel. THIS update to Foreflight gives BARO altitude. You can get violated by the FAA for flying GPS altitude through a class B airspace - especially if there is a rapidly moving pressure system in the area (an instance where your baro altitude could be significantly off from GPS altitude).

Additionally, after contacting Foreflight today I was informed that it WILL use the baro altitude from a Garmin GDL unit. You must be running Foreflight V15.6 or later to have this feature.

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Good to know. I also use the GDL52. Thanks for the info.

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After thinking it over I SHOULD have actually said when the baro-setting is either unusually high or unusually low - THAT'S when your GPS altitude could be significantly off from your baro-altitude. Sorry for the miss-information