Jumpah 0 #1 November 8, 2005 Hey everyone, I was jumping this weekend at SNE and noticed that my altimeter was reading 500 feet less than the guy next to me. I checked with the gal in front of me and confirmed mine was wrong. I have made 5 jumps with it prior, and it was new when I bought it. I was in FL two weeks ago and it worked fine. It has not been dropped or received any damage that I know of. As the plane gained altitude it moved up steady but was always behind everyone else by the same amount, around 500 feet. I gave it a few good taps and it didn't change. Is this a common issue? Should I have re-calibrated it to the mean of the other alti's while we were in flight? I only got one jump in due to a plane problem later in the day, so I couldn't try it again. I was planning on bringing a second alti with me for that jump, btw. Appreciate any advice. New to the sport ps...an audible backup alti is on order. Quote Share this post Link to post Share on other sites IanHarrop 42 #2 November 8, 2005 Best thing to do is to contact the manufacturer - Alti-2 Lara Kjeldsen Office Manager lara@alti-2.com tel.: (386)943-9333 fax: (386)943-9303 IM: lara_kjeldsen (Yahoo!) / LaraAtAlti2 (AIM) web: www.alti-2.com"Where troubles melt like lemon drops, away above the chimney tops, that's where you'll find me" Dorothy Quote Share this post Link to post Share on other sites Jumpah 0 #3 November 8, 2005 Thanks...sent them a note. Quote Share this post Link to post Share on other sites jmp2liv 0 #4 November 8, 2005 Did you remember to check it on the ground for zero before starting the ascent? If not, it may have already been off due to pressure changes in the atmosphere. (Or elevations changes from different DZ's, etc.) Quote Share this post Link to post Share on other sites kelpdiver 2 #5 November 8, 2005 what altitude were you at when you found the discrepency? Up high, that may not be bad, but anywhere near deploy altitude, no good. At least it was reading low! I landed a neptune on the first jump of the day and was thinking - man, what's with this POS? It's reading -300ft! Not a good show for this demo. About an hour later I realized I still had an offset on it for another DZ (Hollister). When you take off, verify that it's at zero and moving. And check someone else's in the 3-5k range - wherever you like to open. Quote Share this post Link to post Share on other sites Jumpah 0 #6 November 8, 2005 QuoteDid you remember to check it on the ground for zero before starting the ascent? Yes. The weekend before I was in FL using it. When I arrived at SNE that morning it was reading -350 or so, so I zero'd it right before getting on the plane. Quote what altitude were you at when you found the discrepency? Noticed it right from the start. I was planning on dumping at 5,500 anyway to do some canopy practice so there was room for error. Quote Share this post Link to post Share on other sites MrBrant 0 #7 November 8, 2005 also something to keep in mind: ALWAYS zero it before EVERY jump. Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". Quote Share this post Link to post Share on other sites Jumpah 0 #8 November 8, 2005 Heard back from the manufacturer, and was told it probably just needs to be recalibrated. Was provided with an address to send it. She also responded to whether I should reset the alti while up in the air, which I'll post here as someone else may wonder the same thing some day... QuoteYou should not adjust your altimeter once you have left the ground, even if it does show a different altitude than other altimeters. It is not uncommon for altimeters to be a bit different at higher altitudes, but still be within tolerance, and show zero upon landing. So, if you set your altimeter which is a touch high, against someone else's whose is a touch low, by the time you get to the ground, there will be a serious difference. If you have any questions about this, please let me know. Quote Share this post Link to post Share on other sites AndyMan 7 #9 November 8, 2005 Quote Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". I've never seen anything remotely approaching "hundreds of feet". Throughout a day, even with changing weather conditions I've not seen more than 60 feet on a day where it was jumpable all day. If it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Zeroing throughout the day is a "nice to have", not a "must have". _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites pilotdave 0 #10 November 8, 2005 Better do it throughout the day if you plan on making any instrument approaches where you need better than 100 foot accuracy. Dave Quote Share this post Link to post Share on other sites MrBrant 0 #11 November 9, 2005 QuoteQuote Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". I've never seen anything remotely approaching "hundreds of feet". Throughout a day, even with changing weather conditions I've not seen more than 60 feet on a day where it was jumpable all day. If it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Zeroing throughout the day is a "nice to have", not a "must have". _Am I have seen close to 500 feet differance one day. We were jumping in the morning, a thunderstorm blew through, we were grounded for about 4 hours, then it was jumpable again. I do agree, it is unlikely that you will normally see this change, but it is possible. For this reason, I always check my altimeter as part as my gear check, and at my DZ, it is a part of a pre-boarding pin check given by another jumper. Quote Share this post Link to post Share on other sites rbanfield 0 #12 November 9, 2005 I saw my altimeter drop by 400 feet while in my apartment with a hurricane 150 miles away and us getting a fair amount of bad weather. If the barometric pressure is still equating to a -500 feet drop in altitude, I would guess its not quite 100% safe to jump anyway as the thunderstorms wouldnt really be that far off. Am I wrong? Quote Share this post Link to post Share on other sites DeNReN 0 #13 November 9, 2005 I have to concur with the others...as I have seen swings of well over 500ft just from barametric pressure.... I just moved to a new house(old house..but new to me)...and noticed a 1000ft differance from the last time it was "zero'ed at the DZ....ASL at the DZ is 124ft..old tin hut is approx 500ft ASL...new house is approx 600ft ASL...was a nice sunny day when I looked ...wishing i was at the DZ. In reality a altimeter can be used a a barometer back to the thread topic..if its off..send it back...from everything I have read on these forums...its one stand up company PS: mine is always within a couple hundred feet of the planes alt and others jumpers alts.(eitherway) Quote Share this post Link to post Share on other sites Erroll 80 #14 November 9, 2005 QuoteI have to concur with the others...as I have seen swings of well over 500ft just from barametric pressure.... Quote I don't think Andy was disputing the fact that one can observe such big changes. His point was that if one does experience such a big change then conditions for jumping are greatly affected (for better or worse). QuoteIf it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Quote Share this post Link to post Share on other sites AndyMan 7 #15 November 9, 2005 QuoteI just moved to a new house(old house..but new to me)...and noticed a 1000ft differance from the last time it was "zero'ed at the DZ....ASL at the DZ is 124ft..old tin hut is approx 500ft ASL...new house is approx 600ft ASL...was a nice sunny day when I looked Wink...wishing i was at the DZ. I think you misunderstand. You certainly do need to zero your altimeter at the start of every day. You also need to zero it when you move to a different location. Indeed in both of these cases, wild swings are the norm. A bright sunny dry day will have a very different pressure than a bright sunny humid day, for example. However, it is entirely unlikely that you need to zero it again and again, throughout the day. Large swings in air pressure only happen when there are corresponding large swings in weather. When large swings in weather happen, jumping either stops, or starts. If a large storm passes, it'd be wise to check accuracy when that happens. It would also be wise to ensure that it is close to zero on every jump before loading the plane. Zeroing before very jump is a "nice to have", not a "must have". I digress. _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites phoenixlpr 0 #16 November 9, 2005 I think its a good practice to check altimeter before boarding. Quote Share this post Link to post Share on other sites JeepDiver 0 #17 November 9, 2005 The morning Hurricane Wilma blew through here in Ft Lauderdale, FL I had sent my Altimeter to 0 the night before the storm. At 8:00am it was reading 1500 AGL Quote Share this post Link to post Share on other sites rasmack 0 #18 November 10, 2005 Now, that's a hurricane! Who needs jump planes... On a side note, you should know better than to go jumping in a hurricane HF #682, Team Dirty Sanchez #227 “I simply hate, detest, loathe, despise, and abhor redundancy.” - Not quite Oscar Wilde... Quote Share this post Link to post Share on other sites bisqit999 0 #19 November 12, 2005 I have a very similar issue with the same altimeter...It seems to be accurate up to about 8000 feet and then it slowly goes higher than everyone elses alti. By the time I'm at altitude it's usually about 500-800 feet higher than everyone elses. It's been like this since I got it.. It always reads zero on the ground. I plan on sending it back to get checked this winter. Seems like its better to err on the high side though. Quote Share this post Link to post Share on other sites adobelover 0 #20 November 12, 2005 I check my altimeter AND my AAD before EVERY jump! _________________________________________ Old age ain't no place for sissies! Quote Share this post Link to post Share on other sites masterrig 1 #21 November 13, 2005 QuoteHey everyone, I was jumping this weekend at SNE and noticed that my altimeter was reading 500 feet less than the guy next to me. I checked with the gal in front of me and confirmed mine was wrong. I have made 5 jumps with it prior, and it was new when I bought it. I was in FL two weeks ago and it worked fine. It has not been dropped or received any damage that I know of. As the plane gained altitude it moved up steady but was always behind everyone else by the same amount, around 500 feet. I gave it a few good taps and it didn't change. Is this a common issue? Should I have re-calibrated it to the mean of the other alti's while we were in flight? I only got one jump in due to a plane problem later in the day, so I couldn't try it again. I was planning on bringing a second alti with me for that jump, btw. Appreciate any advice. New to the sport ps...an audible backup alti is on order. _______________________________________ I've found that to be quite common with that brand. Chuck Quote Share this post Link to post Share on other sites Join the conversation You can post now and register later. If you have an account, sign in now to post with your account. Note: Your post will require moderator approval before it will be visible. Reply to this topic... × Pasted as rich text. Paste as plain text instead Only 75 emoji are allowed. × Your link has been automatically embedded. Display as a link instead × Your previous content has been restored. Clear editor × You cannot paste images directly. Upload or insert images from URL. Insert image from URL × Desktop Tablet Phone Submit Reply 0 Go To Topic Listing
IanHarrop 42 #2 November 8, 2005 Best thing to do is to contact the manufacturer - Alti-2 Lara Kjeldsen Office Manager lara@alti-2.com tel.: (386)943-9333 fax: (386)943-9303 IM: lara_kjeldsen (Yahoo!) / LaraAtAlti2 (AIM) web: www.alti-2.com"Where troubles melt like lemon drops, away above the chimney tops, that's where you'll find me" Dorothy Quote Share this post Link to post Share on other sites
Jumpah 0 #3 November 8, 2005 Thanks...sent them a note. Quote Share this post Link to post Share on other sites
jmp2liv 0 #4 November 8, 2005 Did you remember to check it on the ground for zero before starting the ascent? If not, it may have already been off due to pressure changes in the atmosphere. (Or elevations changes from different DZ's, etc.) Quote Share this post Link to post Share on other sites
kelpdiver 2 #5 November 8, 2005 what altitude were you at when you found the discrepency? Up high, that may not be bad, but anywhere near deploy altitude, no good. At least it was reading low! I landed a neptune on the first jump of the day and was thinking - man, what's with this POS? It's reading -300ft! Not a good show for this demo. About an hour later I realized I still had an offset on it for another DZ (Hollister). When you take off, verify that it's at zero and moving. And check someone else's in the 3-5k range - wherever you like to open. Quote Share this post Link to post Share on other sites
Jumpah 0 #6 November 8, 2005 QuoteDid you remember to check it on the ground for zero before starting the ascent? Yes. The weekend before I was in FL using it. When I arrived at SNE that morning it was reading -350 or so, so I zero'd it right before getting on the plane. Quote what altitude were you at when you found the discrepency? Noticed it right from the start. I was planning on dumping at 5,500 anyway to do some canopy practice so there was room for error. Quote Share this post Link to post Share on other sites
MrBrant 0 #7 November 8, 2005 also something to keep in mind: ALWAYS zero it before EVERY jump. Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". Quote Share this post Link to post Share on other sites
Jumpah 0 #8 November 8, 2005 Heard back from the manufacturer, and was told it probably just needs to be recalibrated. Was provided with an address to send it. She also responded to whether I should reset the alti while up in the air, which I'll post here as someone else may wonder the same thing some day... QuoteYou should not adjust your altimeter once you have left the ground, even if it does show a different altitude than other altimeters. It is not uncommon for altimeters to be a bit different at higher altitudes, but still be within tolerance, and show zero upon landing. So, if you set your altimeter which is a touch high, against someone else's whose is a touch low, by the time you get to the ground, there will be a serious difference. If you have any questions about this, please let me know. Quote Share this post Link to post Share on other sites
AndyMan 7 #9 November 8, 2005 Quote Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". I've never seen anything remotely approaching "hundreds of feet". Throughout a day, even with changing weather conditions I've not seen more than 60 feet on a day where it was jumpable all day. If it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Zeroing throughout the day is a "nice to have", not a "must have". _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites
pilotdave 0 #10 November 8, 2005 Better do it throughout the day if you plan on making any instrument approaches where you need better than 100 foot accuracy. Dave Quote Share this post Link to post Share on other sites
MrBrant 0 #11 November 9, 2005 QuoteQuote Barometric pressure can change greatly even though-tout the day, so, if you set it correctly in the morning, later in the afternoon, it can be hundreds of feet "out". I've never seen anything remotely approaching "hundreds of feet". Throughout a day, even with changing weather conditions I've not seen more than 60 feet on a day where it was jumpable all day. If it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Zeroing throughout the day is a "nice to have", not a "must have". _Am I have seen close to 500 feet differance one day. We were jumping in the morning, a thunderstorm blew through, we were grounded for about 4 hours, then it was jumpable again. I do agree, it is unlikely that you will normally see this change, but it is possible. For this reason, I always check my altimeter as part as my gear check, and at my DZ, it is a part of a pre-boarding pin check given by another jumper. Quote Share this post Link to post Share on other sites
rbanfield 0 #12 November 9, 2005 I saw my altimeter drop by 400 feet while in my apartment with a hurricane 150 miles away and us getting a fair amount of bad weather. If the barometric pressure is still equating to a -500 feet drop in altitude, I would guess its not quite 100% safe to jump anyway as the thunderstorms wouldnt really be that far off. Am I wrong? Quote Share this post Link to post Share on other sites
DeNReN 0 #13 November 9, 2005 I have to concur with the others...as I have seen swings of well over 500ft just from barametric pressure.... I just moved to a new house(old house..but new to me)...and noticed a 1000ft differance from the last time it was "zero'ed at the DZ....ASL at the DZ is 124ft..old tin hut is approx 500ft ASL...new house is approx 600ft ASL...was a nice sunny day when I looked ...wishing i was at the DZ. In reality a altimeter can be used a a barometer back to the thread topic..if its off..send it back...from everything I have read on these forums...its one stand up company PS: mine is always within a couple hundred feet of the planes alt and others jumpers alts.(eitherway) Quote Share this post Link to post Share on other sites
Erroll 80 #14 November 9, 2005 QuoteI have to concur with the others...as I have seen swings of well over 500ft just from barametric pressure.... Quote I don't think Andy was disputing the fact that one can observe such big changes. His point was that if one does experience such a big change then conditions for jumping are greatly affected (for better or worse). QuoteIf it's changing much more than 60 feet, it wasn't jumpable before the change, or won't be jumpable after. Quote Share this post Link to post Share on other sites AndyMan 7 #15 November 9, 2005 QuoteI just moved to a new house(old house..but new to me)...and noticed a 1000ft differance from the last time it was "zero'ed at the DZ....ASL at the DZ is 124ft..old tin hut is approx 500ft ASL...new house is approx 600ft ASL...was a nice sunny day when I looked Wink...wishing i was at the DZ. I think you misunderstand. You certainly do need to zero your altimeter at the start of every day. You also need to zero it when you move to a different location. Indeed in both of these cases, wild swings are the norm. A bright sunny dry day will have a very different pressure than a bright sunny humid day, for example. However, it is entirely unlikely that you need to zero it again and again, throughout the day. Large swings in air pressure only happen when there are corresponding large swings in weather. When large swings in weather happen, jumping either stops, or starts. If a large storm passes, it'd be wise to check accuracy when that happens. It would also be wise to ensure that it is close to zero on every jump before loading the plane. Zeroing before very jump is a "nice to have", not a "must have". I digress. _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites phoenixlpr 0 #16 November 9, 2005 I think its a good practice to check altimeter before boarding. Quote Share this post Link to post Share on other sites JeepDiver 0 #17 November 9, 2005 The morning Hurricane Wilma blew through here in Ft Lauderdale, FL I had sent my Altimeter to 0 the night before the storm. At 8:00am it was reading 1500 AGL Quote Share this post Link to post Share on other sites rasmack 0 #18 November 10, 2005 Now, that's a hurricane! Who needs jump planes... On a side note, you should know better than to go jumping in a hurricane HF #682, Team Dirty Sanchez #227 “I simply hate, detest, loathe, despise, and abhor redundancy.” - Not quite Oscar Wilde... Quote Share this post Link to post Share on other sites bisqit999 0 #19 November 12, 2005 I have a very similar issue with the same altimeter...It seems to be accurate up to about 8000 feet and then it slowly goes higher than everyone elses alti. By the time I'm at altitude it's usually about 500-800 feet higher than everyone elses. It's been like this since I got it.. It always reads zero on the ground. I plan on sending it back to get checked this winter. Seems like its better to err on the high side though. Quote Share this post Link to post Share on other sites adobelover 0 #20 November 12, 2005 I check my altimeter AND my AAD before EVERY jump! _________________________________________ Old age ain't no place for sissies! Quote Share this post Link to post Share on other sites masterrig 1 #21 November 13, 2005 QuoteHey everyone, I was jumping this weekend at SNE and noticed that my altimeter was reading 500 feet less than the guy next to me. I checked with the gal in front of me and confirmed mine was wrong. I have made 5 jumps with it prior, and it was new when I bought it. I was in FL two weeks ago and it worked fine. It has not been dropped or received any damage that I know of. As the plane gained altitude it moved up steady but was always behind everyone else by the same amount, around 500 feet. I gave it a few good taps and it didn't change. Is this a common issue? Should I have re-calibrated it to the mean of the other alti's while we were in flight? I only got one jump in due to a plane problem later in the day, so I couldn't try it again. I was planning on bringing a second alti with me for that jump, btw. Appreciate any advice. New to the sport ps...an audible backup alti is on order. _______________________________________ I've found that to be quite common with that brand. Chuck Quote Share this post Link to post Share on other sites Join the conversation You can post now and register later. If you have an account, sign in now to post with your account. Note: Your post will require moderator approval before it will be visible. Reply to this topic... × Pasted as rich text. Paste as plain text instead Only 75 emoji are allowed. × Your link has been automatically embedded. Display as a link instead × Your previous content has been restored. Clear editor × You cannot paste images directly. Upload or insert images from URL. Insert image from URL × Desktop Tablet Phone Submit Reply 0 Go To Topic Listing
AndyMan 7 #15 November 9, 2005 QuoteI just moved to a new house(old house..but new to me)...and noticed a 1000ft differance from the last time it was "zero'ed at the DZ....ASL at the DZ is 124ft..old tin hut is approx 500ft ASL...new house is approx 600ft ASL...was a nice sunny day when I looked Wink...wishing i was at the DZ. I think you misunderstand. You certainly do need to zero your altimeter at the start of every day. You also need to zero it when you move to a different location. Indeed in both of these cases, wild swings are the norm. A bright sunny dry day will have a very different pressure than a bright sunny humid day, for example. However, it is entirely unlikely that you need to zero it again and again, throughout the day. Large swings in air pressure only happen when there are corresponding large swings in weather. When large swings in weather happen, jumping either stops, or starts. If a large storm passes, it'd be wise to check accuracy when that happens. It would also be wise to ensure that it is close to zero on every jump before loading the plane. Zeroing before very jump is a "nice to have", not a "must have". I digress. _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites
phoenixlpr 0 #16 November 9, 2005 I think its a good practice to check altimeter before boarding. Quote Share this post Link to post Share on other sites
JeepDiver 0 #17 November 9, 2005 The morning Hurricane Wilma blew through here in Ft Lauderdale, FL I had sent my Altimeter to 0 the night before the storm. At 8:00am it was reading 1500 AGL Quote Share this post Link to post Share on other sites
rasmack 0 #18 November 10, 2005 Now, that's a hurricane! Who needs jump planes... On a side note, you should know better than to go jumping in a hurricane HF #682, Team Dirty Sanchez #227 “I simply hate, detest, loathe, despise, and abhor redundancy.” - Not quite Oscar Wilde... Quote Share this post Link to post Share on other sites
bisqit999 0 #19 November 12, 2005 I have a very similar issue with the same altimeter...It seems to be accurate up to about 8000 feet and then it slowly goes higher than everyone elses alti. By the time I'm at altitude it's usually about 500-800 feet higher than everyone elses. It's been like this since I got it.. It always reads zero on the ground. I plan on sending it back to get checked this winter. Seems like its better to err on the high side though. Quote Share this post Link to post Share on other sites
adobelover 0 #20 November 12, 2005 I check my altimeter AND my AAD before EVERY jump! _________________________________________ Old age ain't no place for sissies! Quote Share this post Link to post Share on other sites
masterrig 1 #21 November 13, 2005 QuoteHey everyone, I was jumping this weekend at SNE and noticed that my altimeter was reading 500 feet less than the guy next to me. I checked with the gal in front of me and confirmed mine was wrong. I have made 5 jumps with it prior, and it was new when I bought it. I was in FL two weeks ago and it worked fine. It has not been dropped or received any damage that I know of. As the plane gained altitude it moved up steady but was always behind everyone else by the same amount, around 500 feet. I gave it a few good taps and it didn't change. Is this a common issue? Should I have re-calibrated it to the mean of the other alti's while we were in flight? I only got one jump in due to a plane problem later in the day, so I couldn't try it again. I was planning on bringing a second alti with me for that jump, btw. Appreciate any advice. New to the sport ps...an audible backup alti is on order. _______________________________________ I've found that to be quite common with that brand. Chuck Quote Share this post Link to post Share on other sites
