Cypres maintenance

[Alborne 3]

Is maintenance on the newer cypres voluntary? If so what’s your opinion on forgoing the 5 and 10 year maintenance cycles?

[danornan 79]

You can, but I'd be concerned with where you store it and how often you have jumped it between services.  Also remember that when it's needed, if it doesn't work, you will probably die.

 

[BIGUN 1,296]

2 hours ago, Alborne said:

If so what’s your opinion on forgoing the 5 and 10 year maintenance cycles?

First, take your current annual income and factor it out over thirty years at a compounded 7% increase. Once you determine the total value; ask yourself if saving a few bucks to reach that is worth it.  

[pchapman 279]

Yet lets face it, skipping the maintenance - and increasing total lifetime-  is what may be saving Cypres. Otherwise, everyone was buying Vigils or M2's.  Cypres' 12.5 years and 2 servicings sucked compared to Vigil's 20 years & 1 servicing, or M2's 15 and 0.    Cypres' new 15.5 and 0 is competitive, as have been the prices of all 3 models in recent years.

12.5 and 2 servicings made sense when it was the pioneering electronic AAD and everyone was cautious about AAD's, but the market didn't want that king of careful, cautious, expensive approach once there were decent competitors. 

(And we also had to get past the era in the 2000's & 2010's when everyone was having recalls & service bulletins, Vigil by far the most of all. The real AAD-war era!   Cypres was known for its arrogance in denying problems early on; while Vigil had so many service bulletins, they changed their numbering system so you'd forget how many they previously had.)

I know there's stuff in Vigil & M2 manuals about mandatory yearly comparisons to aircraft altimeters to confirm accuracy of at least the pressure sensor.... That very few ever talk about.... But what percentage of jumpers actually do those yearly checks?   1%?  5%   (Maybe there are some high end full-service rigging shops that'll do it for you? If those exist, good for them.)

I still figure Cypres has the edge on quality of algorithms, and that's what I buy, but most rigs out there nowadays in my area have Vigils. Maybe Cypres' are making a come back, I dunno, but I'd expect them to.

[kleggo 145]

keep in mind it took SSK FOUR MONTHS to service and return my bomb this year.

[IJskonijn 45]

13 hours ago, pchapman said:

I know there's stuff in Vigil & M2 manuals about mandatory yearly comparisons to aircraft altimeters to confirm accuracy of at least the pressure sensor.... That very few ever talk about.... But what percentage of jumpers actually do those yearly checks?   1%?  5%   (Maybe there are some high end full-service rigging shops that'll do it for you? If those exist, good for them.)

Mars has it in their current manual (p38), with a limit of +- 15 hPa allowable deviation.

Few of the units are around in the Netherlands, I own one myself and I check it during every repack by comparing it to published barometric pressure of the closest KNMI station (our national meteorological institute). If you go that route take into account both your own altitude (ASL) and station altitude + whether or not it is corrected to MSL. Since at sea level 1 hPa pressure difference is approximately 8 meters altitude difference, I find +- 15 hPa quite a big allowable range. I've never seen any differences larger than 1-2 hPa.

Vigil can also show current barometric pressure, and I check them the same way as I do Mars AADs. But their manual says nothing about checking the pressure reading, and they responded by e-mail to me that the pressure does not need any checking by field riggers... The physicist in me finds that baffling, because why else would you include the ability to read out the measured pressure? In practice, I've never seen any Vigil units with more than 1-2 hPa deviations either.

To my knowledge the Cypres doesn't offer any way to read out the actual air pressure measured.

[pchapman 279]

Thanks IJskonijn for the correction.

Vigil in the early days did "recommend" yearly pressure checks on the Vigil II's in early manuals but seems to have removed it from the manuals somewhere along the way (for the II, 2+, and Cuatro) as far as I can see in a quick check this morning.

So to correct my previous statements:

The Vigil does not require any annual pressure comparisons to an altimeter.  (Used to, but not for quite some time) (But yeah it sounds like a good idea to do occasionally since it gives a pressure readout)

The M2 does require an annual inspection of the entire unit (which logically would be rigger performed) and annual pressure comparison to an altimeter.

Technically that inspection also includes checking that the 'altitude lock release' occurs at the appropriate altitude during climb (e.g., 1475 ft) (i.e., center line between the arrows disappears). Which pretty means having the rig in a climbing airplane with someone watching the M2 control unit. Not sure who is doing that regularly!

And by altimeter, they mean something like an aviation altimeter with high accuracy.

Good luck for the average skydiver being able to figure out how to actually get a reference hPa reading to compare with what the M2 says.

The long version of that: There are hPa to mmHg conversions to do here in North America, plus aviation altimeters show the equivalent ISA pressure at sea level and not the current level at airport elevation. But you could set the alti to 29.92 mmHg and get pressure altitude and use an ISA atmosphere chart or formula off the web to convert to actual pressure. (I have seen web sites with Station Pressure for weather stations but then one better be at that weather station, again unless one is great at using ISA tables.)    It all gets kind of messy and even as a private pilot I'd have to puzzle through it. Or am I missing some shortcut?

Also, in recent years M2 had changed their lifetime from 15 years (their traditional life), to 15.5 years (probably to match Cypres). Just one more thing I noticed.

All good with all that?

There's always something that changes in manuals....

[gowlerk 2,190]

1 hour ago, pchapman said:

The Vigil does not require any annual pressure comparisons to an altimeter.  (Used to, but not for quite some time) (But yeah it sounds like a good idea to do occasionally since it gives a pressure readout)

The M2 does require an annual inspection of the entire unit (which logically would be rigger performed) and annual pressure comparison to an altimeter.

I generally check one AAD against another AAD. If there was a difference beyond the spec then I would find a third one to see which one was bad. But that has never happened so far.

[IJskonijn 45]

I don't see any need written in the manual to check M2 pressure readings relative to an aircraft altimeter or to check the altitude lock release during climb. I would consider such checks beyond the annual inspection, unless the annual inspection shows reason to suspect the device of malfunctioning. But in that case I'm already contacting the manufacturer about it anyway.

The text in the M2 manual (as of 10-7-2024) is:

Quote

9.4. Annual inspection
The m2 multi device must undergo a periodic inspection at least once every 12 months; the inspection is usually performed by the rigger when repacking the reserve parachute. The inspection shall be recorded in the device Technical Log. The user is always responsible for performing this inspection and it depends on him whether he performs the required activities himself or whether he has someone else do it.

9.4.1. Inspection procedure
a) Inspect the device visually for any visible mechanical damage, pay special attention to the connection cables, filter, control unit and cutter.
b) Check the battery (under the letter “b” in the device INFO menu, Section 5.4.)
c) Check displayed pressure (under the letter “P” in the device INFO menu, Section 5.4.) Perform the pressure check by comparing it to another precision instrument that shows barometric pressure. It is also possible to use the actual pressure at the airport. The deviation shall not be greater than +/-15 hPa.

My own procedure is thus to check the device reading ("P" in the info menu). Since I am most often in Hilversum, the closest weather station in the Netherlands is De Bilt, so I check its pressure reading in the list here (https://www.knmi.nl/nederland-nu/weer/waarnemingen). I assume the 10-minute average published there is close enough to the direct measurement. The published readings there are corrected to MSL, and Hilversum Airport (EHHV) is just 1m above sea level so I expect the M2 to read approximately 0.1 hPa lower (my home is at 5m ASL, so ~0.7 hPa lower reading). The remaining deviation is sensor deviation + lateral deviation due to weather systems. The isobars in a weather map will give an indication of the latter, but with a +- 15 hPa allowed deviation I rarely even bother with that step unless the weather is truly wild (=very close isobars). As I've said, so far I haven't seen more than 1-2 hPa deviation in any device (M2 or Vigil) that I've checked.

Checking these units may take some figuring out for a rigger's specific situation, but once figured out it's really easy. Adds like 1 minute to my flow of an entire I&R.

 

Oh, and to get back to the original topic: Cypres maintenance is voluntary since units made in 2016. In my opinion, all three major AADs are sufficient, and a Cypres is the priciest option for slightly more quality and slightly better track record (open to discussion). If you pick the priciest AAD on the market anyway, I suggest to not cheap out on the factory maintenance and do it anyway even if not mandatory.

Edited July 10, 2024 by IJskonijn

[bart400us 0]

I have one at the (Cypres) service center.  Rigger told me 6-8 weeks.

Seems like it would be best to time your required maintenance during your drop zones down time.

Lot of drop zones that would be winter.  Eloy, Arizona, summer!

I visited Skydive Monterey (California) during the hot Eloy summer.

I could not even feel the parachute opening at Monterey!