North site AOO is a two nautical mile radius for 20,000' AGL and below, and it is a five nautical mile radius when the 35,000' AGL windows were used.

So a 4 mile cylinder to 20K and a 10 mile cylinder to 35K. Excellent

W

Following John W.'s logic that it is really hard to drift 15,000' away on a 9k boost another data point is John Bixler's Junior flight on Friday. He flew a 54mm diameter rocket to 22,312' and recovered 1.72 miles due east. Now a 54mm rocket has a lot more surface area, as well as a bigger main parachute to drift on and didn't go nearly as far as 15,000' away. Just another data point.

Edward

Ed it was only 1.3-1.5 miles away not 3. a lot of the points on the map are not clear as to what they are.

I'm glad to see that Adrian is not looking at temperate 'adjustments' for any record claims. As pointed out, this would be a huge difference to the altitudes seen from altimeters that have been used for Tripoli and club records over the last decade or so. In some of the posts I have seen claims that temperature adjusted data is about 12% higher than non-adjusted. If this were the case then it would be a very apples-to-oranges comparison.

I should point out that there are "temperature compensated" pressure sensors, and "uncompensated" sensors. I am not aware of any rocket altimeters that currently use the uncompensated type. Warren, when you talk about your discussions with Jim Amos, I assume that he is talking about his use of an "integrated" (temperature compensated) sensor as opposed to any temperature compensation he is doing in his firmware.

My personal desire is for altimeters that are similar in performance as opposed to extreme MSL accuracy. As Scott pointed out, this is a hobby. I'm not landing a 747. What also remains to be seen is if there can be manufacturing consistency on a $100 part. It only takes a few millivolts of noise to make a huge difference in altitude. What I'm saying is that I want repeatability and consistency as opposed to extreme accuracy. If new altimeters come out that are more accurate and temperature adjusted, then there should be a new set of records, or a new understanding of how the records are set. The Parrot may be this new product in a new world of altimeters. Right now the Parrot is still in beta test and there is only one person using it to report altitudes or claim records. Given time this may be the direction of all altitude records.

Finally, I've been thinking about my earlier comment about "witnessing" the flight if I were the LCO or RSO. I would not in good conscious be able to witness this altitude shot for a Tripoli record. All I could agree to is that I saw a stable rocket presented to the RSO, the skies were clear, and the rocket was launched. Beyond that nothing I say should make any difference (just like in this forum).

The discussion I had with Jim was more related to the fact that the standard atmosphere model is calibrated at a specific temperature - I can't recall what it is, but I think it's right at freezing. However, most flights are in warmer weather and compensation is necessary to adjust the reading for the warmer temperature. This is above and beyond any internal compensation provided by the sensor. Jim achieves this by normalizing the data for 70 degrees or thereabouts and told me that all the manufacturers adjust the SAM based on that. Of course, I may have misunderstood the conversation.

As for witnessing a record flight - I believe the rules state that two NCR members in good standing must witness the altitude reading directly off the altimeter immediately upon recovery. I believe that alone would disqualify the Parrot unless Adrian were to do the data download at the LCO table immediately upon recovery. My biggest recommendation to him is to provide a direct reading of altitude either via beeps or flashing LED as other manufacturers do or a plug-in LCD display that reads the raw altitude. I think it's an excellent product, but as it stands I see far too much push-back due to the after-action data download required to read the altitude. I very much like the accelerometer data that goes with the baro data though.

W

My biggest recommendation to him is to provide a direct reading of altitude either via beeps or flashing LED as other manufacturers do or a plug-in LCD display that reads the raw altitude. I think it's an excellent product, but as it stands I see far too much push-back due to the after-action data download required to read the altitude. I very much like the accelerometer data that goes with the baro data though.

W

If Adrian logged in using hyperterminal and showed the raw data from the altimeter without pulling it into excel or the like would that be acceptable? That's not really any different than a plugin LCD type display. You could build an LCD that does a small 1.2x multiplier on whatever the real output is and cheat that way too.

To me, Adrian's altimeter presents more than enough data to support itself, even with the processing. Its almost as if the altimeter is being dis-regarded because its too accurate or provides too much data at a granular level.

I don't dismiss everyone's concerns about data being presented after the fact, by the manufacturer, etc. As far as the output though, it think that should be a non-issue.

Chris

So after reading over this I think there probably is a simpler solution than banning an altimeter flown by the manufacturer. When digital photography came of age it just so happened that all truth in photograph was lost. You really couldn't believe your eyes anymore because a good enough person could manipulate a photo seamlessly. This had an impact on crime scene photos and ones presented in courts. How could you trust the photos? Well, every camera sensor is different and all have a few dead pixels here and there and some that are hot, etc. The one I'm familiar with (Canon) took the step of having a kit where you took some photos under specific lighting and backgrounds, and those were your template images. Any photos you took after were compared to those to determine if they had those same dead and hot pixels. It would be really hard to alter an image and not wipe out a couple of those - so it was easy to verify. It also encoded other camera specific information into it.

Why can't something like this be developed for altimeters? Before the flight you go to the LCO, RSO, or an observer and they type in their password into the altimeter programming software. This encodes the data on the altimeter so it can only be read with that password. Then we have a standardized program for interpreting the data. You take that altimeter to the LCO and observer and download and decode it. That way the owner doesn't have control over the datastream.

After writing all this it seems like a lot for a hobby...but who knows....

Edward

I'm all for Adrian's Parrot to be honest about it and I do believe it is more accurate and provides additional data in the form of the 3 axis accelerometer to back up the baro altitude.

That said, I don't believe TRA accepts manufacturers flying their own hardware on record attempts. I believe I'm going to wait to see what shakes out with the TRA Records Committee before I do anything about NCR rules - they stand as they currently are until then and even then it will take a discussion of the Executive Committee and some of the stakeholders including John Wilke, Adrian and perhaps others with an interest in this issue before any rule changes are made.

Warren

I have an inherent conflict of interest, I wasn't there, and I recuse myself. I'm sure smarter folk than I will apply the rules (we do have rules somewhere) and whatever they decide, go for it. This is a hobby, not a grand jury 8)

I may have a somewhat different take on the record list than some people. Some view it as a contest like the upscale contest, in which it's possible to exclude some people from participating. I view the list as a place to record what have been the highest undamaged flights for each motor class. Every flight that is recovered safely can either be proven to be the highest safe flight that has ever flown, or it can't. And if someone brings forward proof that they had the highest flight, then either they really had the highest flight, they made an honest mistake, or they are a liar. If a flier who broke the record didn't lie or cheat or have an inaccurate reading, but that flight isn't on the list, it doesn't mean that the flier didn't break the record, because his or her flight certainly did. It's just a failure of the record list to accurately record the highest flights.

From this perspective, the only reason to exclude manufacturer's flights from record lists, when they use approved altimeters with valid-looking data, is if there's reason to believe that they cheated. Not that it's possible for them to cheat, but that they did cheat. This is why I took it personally at first when Tom Rouse originally refused to put my record-breaking F flight on the TRA list. I interpreted the ruling as saying that no manufacturer can be trusted to submit an honest record application form, a policy which I found to be insulting and absurd.

In the meantime, I've come to understand that some people view the record list as a contest, with rules for participation that mean that a record-breaking flight from an excluded participant just doesn't count. So I don't take it so personally any more. It's really just a fundamental difference of opinion about whether the record list is a contest from which some people are ineligible to participate, or an attempt to document what has actually been achieved in high rocket flights. The gatekeeper for each type of list has to decide what kind of list they intend to maintain.

I had the same thoughts about a conflict of interest, but on the other hand technology normally gets driven by a person which can not acomplish his desires when other alternatives are not available.

Be that as it may, after trying to figure out how to make the Parrot work, with little success on my part, I find it too complex to use for getting a simple altitude, and I just don't want to spend time playing with a laptop in the field. I like the fact that the design is so small, but I would LOVE to just be able to turn it on, fly it,and get instantaneous feedback, and if lost and the battery dies, have the altitude recorded so I can find out what it was.

So, beeps would solve my problem and the concern of getting a validation at the RCO table. I am fairly certain that the NAR would not approve of getting a result after a recovery if the rocketeer went back to the pits first. They were real anal at NARAM 50 to insure they saw motors before they were placed in the rocket (with the initials of the check-in folks) and afterwards, and recorded the serial numbers of weighted payloads and eggs. Rockets had to be returned to the RCO table before the end of the day (8:00 PM) to count as a new altitude or timed duration record. The rocket had to be dissasembled in front of the RCO, to verify the parts as well. One altitude record was taken away from an A division young lady because her father put it on the rod and launched it, then recovered it all while she was doing range duty.

So rev 3 needs beeps to be readable while the rocket is still intact... ...for me at least, but also to eliminate concerns of others and to improve its future marketability.

As an afterthought, I proposed in my R&D entry at NARAM 50, that for the NAR to accept altimeters for record attempts, to get rid of the need for theodilites, that a pressure chamber be present at a meet, and every altimeter compared to a 'gold standard' altimeter for that day. Any percent of variance to the standard would be added or subtracted from the altitude reading to establish the actual meet results. Competitors would have their altimeter serial numberd, calibrated with its offset and approved before competing at that meet, or season.

Adrian, I do want to ensure to ensure you don't take any of this discussion personally - at least on my part. I have never thought cheating was even a part of this discussion, at least as far as you are concerned.

As I've said before, I believe your altimeter has a much better chance of being more accurate than most of the commercial units out there - certainly more so than any I own.

That said, the lack of instantly readable results is probably the biggest obstacle you face from a variety of perspectives:

1) While it's great to have downloadable data, the lack of instant readability post-flight will cause problems such as Mike Konshak relates above for NAR contests and for other contest environments. The downloadable data is great stuff, but the download/post-processing cycle is viewed askance by some as to prone to manipulation - not necessarily by you, but the process doesn't conform to chain-of-evidence standards as the results require interpretation and possible corrections based on the totality of the data.
2) Level playing field issues - far from everyone is capable of designing and manufacturing an altimeter. A number of folks I've talked with are very taken with the idea that all altitude records be flown with the same model/brand of altimeter or even as James discussed, the same set of TRA-owned and certified altimeters. I personally find the logistics of that somewhat daunting, but the sentiment is definitely there.
3) I've also heard the complaint that the Parrot is an unfair advantage due to its light weight and lack of a heavy external battery when compared to the average flyers' Missileworks or Perfectflight or Adept with an external battery bothers them.

All in all, I'd like to see the Parrot evolve a bit - absolutely keep the accelerometer, rechargable battery, downloadable data and the small size and weight... but some sort of direct read-out that can be turned over at the LCO table immediately after flight without a laptop is a necessity for acceptance in contest use.

Warren

3) I've also heard the complaint that the Parrot is an unfair advantage due to its light weight and lack of a heavy external battery when compared to the average flyers' Missileworks or Perfectflight or Adept with an external battery bothers them.

Actually this is the differentiator that makes the Parrot so attractive to fly, in that it fits in an 18mm tube and weighs so little. This is not unfair, by any means, its an evolutionary step in progress and technology and just pushes the market in a new direction, and increases the possible acceptance of use in other venues. No one wants to fly the exact same thing and manufacturers that don't come up with competitive versions will lose out (assuming the market is there). If weight and size are the main criteria, then the perfectflight would be unfair when compared to missleworks and Adept.