shadeland

What's the turnaround time for replacement parts? Handles, freebags, etc. The company is based in SA, are there US-based distributors?

Joellercoaster

I don't think anyone has addressed this in the thread yet so I'll have a go.

The word "elliptical" is certainly a marketing term, so you should take it (and literally anything else you read in a canopy blurb that's not a technical spec or a hard jump number recommendation or a max weight) with a huge grain of salt. But! It does have some use as a term used by skydivers to classify canopies, so I'll have a go.

Ram air canopies started off rectangular - and some of them still are: Navigator, Silhouette, Triathlon are all still made and still popular. Some people (including me sometimes) still jump the original Sabre, though it's not made any more. Colloquially, we call these "square".

Then manufacturers discovered that if you tapered the ends, they would turn faster (and thus dive harder) and fly more efficiently, and maybe quicker through the air due to reduced drag. This is the "high performance" part of ellipticality.

When tapered in a small way, this contributes mostly only good things to an otherwise square canopy - snappier turns, better glide and possibly flare (although it tends to make openings a little more wandery). Some manufacturers refer to these as "lightly elliptical" or "semi-elliptical", and they include wildly popular canopies such as the Sabre2, Pilot, Safire2/3, S-Fire, Spectre and many others. Confusingly, some manufacturers refer to things in this class as "elliptical" or even "fully elliptical", though it's not common.

Tapering beyong this point keeps upping the performance factor in terms of speed and roll and agility, but now you are starting to pay for it. Quick to roll and dive can mean quick to get into trouble - and highly tapered canopies have a tendency to oversteer and/or stay diving once you stop pulling things. If you get cut off in the pattern under your aggressively tapered Mamba, you need to have your reflexes under control and not yank on a toggle to evade, or you might find yourself in a bad place you're too low to get out of again. They are also definitely more prone to bad behaviour on opening! Popular canopies in this class include the Stiletto, Mamba, Zulu, Crossfire2/3, Katana and X-Fire. This is what people generally mean when they say "fully elliptical", or simply "elliptical" for short. There are lots of different shapes in this class, but they all have a noticeable taper on one or both edges.

NOTE: Some places have hard jump number requirements attached to canopies in this group, and for strong reasons.

(All modern cross-braced canopies are, of course, fully elliptical. But those are a whole 'nother thing.)

There is a lot of subtlety I'm missing out here - the models in my groups don't all fly alike and there are plenty or other factors involved, like steepness of trim, reliability of opening and recovery arc, that differentiate them. But, I hope this has answered your question about the word and how it's generally used, a little more directly.

Joellercoaster has the right answer here. To suppilment this, and from John Le Blanc's talk, I put together diagrams of planforms from various canopies for my canopy course.

The first image shows three planforms. The next shows you what they represent. Even the navigator is tapered, and would probably be considered "semi-ellipitcal". Not many non-reserves are rectangular. I can't think of any modern canopy that is.

Fun fact: The original Sabre is completely rectangular: No tapering.

SethInMI

***
They're faced with somewhat incompatible (at least from a market perspective) requirements from a ram air persecptive: The minimum max load to be tested is 220 lbs, yet the total speed must be under 36 ft/s (25 MPH).

It is interesting that they decided to split up the requirements, as I read it, you can't do that, the 220 lb test must pass all requirements, so it would not be possible to certify small reserves without a waiver of some kind.

I agree that does not make sense for ram airs, esp since wind speed makes groundspeed so variable, so I just want to know the descent rate. What is the glide ratio of a typical reserve with brakes stowed?

Regarding the max weight for my PDR143, the manual has not caught up with the website apparently, as it still shows a max of 171lb. I agree that is not unusual, still I wonder if my incapacitated stowed landing is survivable or not under it.

This whole conversation started from someone saying that they believed the Optimums landed faster compared to other reserves. The original basis for that belief was that they learned form PD that PD had obtained a waiver from the FAA to allow a faster overall speed or descent speed.

I think the waiver probably came for a different reason, the reason we're discussing now.

I think that it wasn't the PD Optimums were faster, it's that under C23D there was that incompatability for ram air reserves. So I believe they obtained a waiver for both PD Optimums and PD Reserves, and the same is true for the other reserve manufacturers who tested under C23D (otherwise they could not possibly have C23D certified reserves under about 180 sqft).

Perhaps your reserve was an earlier version of the PDR that was tested under a different TSO? Or they just revised the speeds based on new information.

As to whether your landing would be survivable, I suspect yes in descent conditions (not downwind, clear and open field, dirt and not concrete), but I don't have really any basis for that other than eyeballing my approach speed on my Optimum 143 (WL 1.4). So my confidence is not high there. Though you'd probably break stuff.

Quote

So why did they choose 1.2WL as the regular max weight? is that what is needed to satisfy the 24ft/s descent rate?

Icarus pretty much says that on their Icarus Reserve page:
The weights listed below are MAXIMUM weights required to comply with all certification requirements set under TSO C23d and ETSO C23d for minimum(1) load and maximum allowable total velocity(2).
1) SAE8015b requires minimum weight to be demonstrated of 255 lb
2) SAE 8015b requires a maximum total velocity under open canopy of 36 ft/s


They're faced with somewhat incompatible (at least from a market perspective) requirements from a ram air persecptive: The minimum max load to be tested is 220 lbs, yet the total speed must be under 36 ft/s (25 MPH).

That probably makes sense for emergency round rigs, but with those requirements on a ram-air you wouldn't be able to have a canopy smaller than about 180 sqft.

Quote

It does give me pause to see that for my PDR-143, the max weight is 171lb, so I am overloading at 200lb suspended weight.

I show the max weight for a PDR-143 based on their site to be 200 lbs for expert (254 lbs do-not-exceed).

http://www.performancedesigns.com/products/pdreserve/

That would likely exceed 36 ft/s. By how much? I don't know. You're at 1.4 WL, which doesn't sound too crazy for a controlled landing. But a no-input landing might be different.

pchapman

Hang on, I always thought that the TSO requirements had to be met at the TSO weight, not at whatever the company "recommend".

Or is that incorrect?

So if a company says "don't jump this 120 at over 160 lbs", that's just a recommendation which may be conservative or not. What matters is that the canopy is for example certified to 254 lbs -- and that's where the velocity requirements apply.

PD is more liberal than some companies in what they 'recommend'. That's due to canopy design in some cases (eg comparing to an old school Raven), while in other cases it may be just less conservative. (eg modern, heavy duty reserves like the Nano or Speed, having low 'maximum' weights if I recall correctly -- sorry no time to check manuals right now).

Some may call that 160 lbs the maximum, or maximum suggested or maximum recommended, or some other term, where each company has its own wording.

But the TSO weight (eg 220, 254, or 300 lbs) is the one that is the real weight that matters to the FAA. Isn't it?

You may be right, but I think the overall TSO weight mimnum (220 lbs for C23d) would put the PDR 99/PD Optimum over the limits for descent and total speed.

(found AS8015 here: http://avstop.com/ac/prh/appendixa_27.html)

4.3.7 states that descent rate shall not exceed 24 feet/s (~16 MPH), and total speed shall not exceed 36 feet/s (~24 MPH) in unaltered post deployment (brakes stowed).

It sounds like they got a waiver for that particular requirement for both PDR and PD Optimum. Icarus did not (though they may have gotten a waiver for minimum demonstrated weight).

From Icarus Reserve page: "The weights listed below are MAXIMUM weights required to comply with all certification requirements set under TSO C23d and ETSO C23d for minimum1 load and maximum allowable total velocity2."

JerryBaumchen

Hi Mark,

Quote

PD Optimums are certificated to the standards of TSO-C23d/AS 8015B.

I have posted about this before on this site.

At the 2005 Symposium, a friend and I were sitting in a restaurant with one of the 'major players' of PD. During the course of that discussion, he informed me that PD had gotten/obtained an exemption to the 'total velocity' req'ment of the TSO standard because their Optimum canopies exceeded the standard.

By how much, I have no idea.

I do not have anything in writing regarding this conversation. I was not told to keep this information to myself.

Jerry Baumchen

PS) I just did a quick review of all of the TSO standards & 'total velocity' first comes up in C23d, AS8015, Rev. B. It states ' . . . the total velocity shall not exceed 36 ft/s (11.0 m/s), in an unaltered post deployment configuration . . . ' Note that this is airspeed and not ground speed. If the dummy or you are going downwind, you will possibly be exceeding these limits.

I think there's an answer (or at least, an incomplete answer) to my original question: TL;DR Optimums would fly slower than their lower sized PDR counterpart. A PD Optimum 160 would (all things being equal) fly slower (total velocity, in both vertical and horizontal component) for a given wingloading than a PDR 143.

Jerry had learned at a symposium at the Optimums exceed the TSO standard for total velocity, and that may be the origin of the assumption (a reasonable one) that Optimums descend faster than non-Optimums (or other canopies).

I believe now that not the case. I think that both the Optimums and current PDRs also exceed the TSO standard for total velocity, as demonstrated by their maximum allowed weight. If you look at the Optimums and PDRs, they both allow WL around 2.0. I have to imagine that 36 ft/s (24 MPH) will be exceeded on almost any wing at 2.0.

The Aerodyne Smart reserves also allow maximum weights that put WL above 2.0.

Interestingly enough, the Icarus reserves and Icarus Nano reserves both have maximum wingloadings at 1.3ish. My guess is they didn't get a waiver for the total velocity.

I would speculate that the waiver was granted because typically the pilot of the wing can flare and place the total velocity well within standard. If no inputs are made though, the landing could of course be bad.

With that, my assumption now is that yes, an PD Optimum of a higher size will lower your descent speed compared to a smaller wing (PDR one size small). More data is needed however.

rjklein4470

FYI, you can demo the reserves from PD. In the past I have always jumped my reserve as a demo. So if and when you have to goto your handles, that little voice in the back of your mind is gone.

Years ago I was flying a " Nova" this canopy will date me, lol. I had a small rip in one of my end cell's. About that time the NOVA was known to acting funny in turbulence low to the ground, collapsing. Even though MY NOVA with the rip was acting fine at altitude, flair was fine, turned fine, recovered fine, I still decided to chop it.

I had several jumps on my reserve as a demo, so in the end it was the right choice.

I sent my Nova back to Glide Path for the repairs, and they said that they would not repair it, but would replace the canopy or give me my money back. This is when the news of the canopy collapsing started to spread so I had them send me a check.

I may just do that later this year with a PDR 113 and Optimum 126 and take along a Flysight.

gowlerk

I guess I just think about this issue differently. I think of my wing as my glider. Like it is an aircraft. Because it is. I consider myself a pilot under it. Like any other aviator I accept a certain amount of risk when I leave the surface of the Earth and play in the sky. If I get into a situation where my aircraft is going to land uncontrolled I do not have a great expectation that I will survive. If somehow I do survive I fully expect to be badly injured. What other aircraft could save me in such a situation?

I don't think that the manufacturer of my wing is responsible for making my wing so slow and boring as to prevent that. And I'm not willing to carry a large enough reserve wing to prevent it.

A pilot emergency or bail out rig is also covered by the same rules. Most of them are rounds and most pilots have never flown a ram air parachute. If you want the largest chance of surviving an uncontrolled landing get a round reserve. But it is far more common, by a large factor, for skydivers to be in control of their reserves. Life is full of design compromises. You have to choose your own sometimes. I choose to play the odds that work for me.

I don't disagree with anything you said there. I follow the same outlook for the most part.

No gear can prevent a bad outcome in all situations, however we can improve our chances with the choice of gear (AAD versus no AAD, helmet versus no helmet, snag-resistant camera mounts, etc.) The fundamental question I'm asking is are we bettering our chances with LPV reserves versus standard.

I've heard more than once that the Optimum flies as fast (horiztonal+vertical) as a PDR one size smaller, negating the benefit of having more fabric over your head (the assumption that more fabric over your head leads to a slower speed, resulting in lower kinetic energy when impacting the big-blue rock or structures upon it).

I'm asking

A) Is it true (while I've heard it said, I've seen zero data to support it)
B) More generally, can we better our outcomes in an unconscious scenario with a size larger reserve

My assumption on B has been that yes, more fabric the better. If that's not the case, then there's no need for an LPV reserve (or at least, no need for an Optimum). I'm confident I can safely land a reserve several sizes larger than my current one when conscious.

Again, I fully accept that unconscious scenarios are not ideal, and could lead to bad outcomes. But they do happen, they are survivable (with a little luck), otherwise AADs wouldn't help much.

To what degree can we help our chances, however, by a size larger reserve? Is the delta between a size so small that it doesn't much matter? Or are we doubling our chances? I suspect the truth is somewhere in the middle, but we really don't have much to go on.

sundevil777

******Not helpful to repost. Kinetic energy is still not all that is important. Better to just keep it in one thread and adjust the discussion.

I would say kinetic energy is the only important factor. Those are the forces on the body at impact with the ground. Specifically, I'm referring to unconscious, no input landings (with brakes stowed). There's a lot of factors involved in those forces, how much and how they're spread out (hitting the ground versus hitting the sider of a building, for example) but it starts with the forward speed (horizontal and vertical component) of the reserve in question.

Kinetic energy is NOT the only important factor. Hitting at a shallow angle is of course very different than straight down. Both scenarios could be at the same speed, so same kinetic energy.

Fair point, but in this case kentic energy is the primary factor we have influence while unconscious: the size of our reserve. Glancing blows (level impact) or direct blows (side of building) will influence outcome as well, but that’s more luck of the draw.

LeeroyJenkins

Yeah, it will work. It is just a docile canopy.

It would seem that's not the case. Among other caveats from the FAQ: "For this reason, we recommend that you have at least 50 jumps on a canopy (landing accurately and comfortably on your feet) that is approximately two (2) sizes SMALLER than the Horizon you plan to use for wingsuiting."

Also: "Performance Designs recommends utilizing the Horizon for the purpose that it was designed and developed for. This will help ensure that you get the best performance and longevity out of your Horizon while using it for wingsuiting."

So, probably not a good choice for non-wing suiting given the OPs status as non-wingsuiter. PD does have the Silhouette, which is a lower pack volume main apprpriaate for general jumping and beginners (at the appropriate wing loading).

For low bulk regular jumping, there's Aerodyne Pilot in ZPX (about a size smaller) and UltraLPV (maybe 2 sizes smaller, not sure). The same for the Pilot 7 (which is good for wing suiting, but Aerodyne says its also good for regular jumping).

I've seen a few ZPXs around, but not the UltraLPV.

sundevil777

Not helpful to repost. Kinetic energy is still not all that is important. Better to just keep it in one thread and adjust the discussion.

I would say kinetic energy is the only important factor. Those are the forces on the body at impact with the ground. Specifically, I'm referring to unconscious, no input landings (with brakes stowed). There's a lot of factors involved in those forces, how much and how they're spread out (hitting the ground versus hitting the sider of a building, for example) but it starts with the forward speed (horizontal and vertical component) of the reserve in question.

JerryBaumchen

Hi Mark,

Quote

PD Optimums are certificated to the standards of TSO-C23d/AS 8015B.

I have posted about this before on this site.

At the 2005 Symposium, a friend and I were sitting in a restaurant with one of the 'major players' of PD. During the course of that discussion, he informed me that PD had gotten/obtained an exemption to the 'total velocity' req'ment of the TSO standard because their Optimum canopies exceeded the standard.

I was looking at the maximums for various reserves. The PD Optimum 126, for example, would put me personally at about 1.5 WL. The stated never exceed maximum is 254 lbs, which would be about a 2.0 loading. My guess is that at a 2.0 loading that would exceed the TSO standard for landing speed (but that's just a guess).

Compared to the Icarus Nano 126, the maximum weight is 167, which is about 1.3 WL. That is probably under the TSO limit (again, just a guess).

gowlerk

There has been a lot of talk about unconscious landings lately. My feeling is that in this situation you are in a world of trouble anyway. Ram air canopies are not forgiving of uncontrolled landings. You would be far better off under a round parachute than a ram air. But that is not practical in the skydiving world.

One size larger or smaller is not going to make a big difference. If you want to feel safer in this rare circumstance you really should have at least a 250 sq ft canopy. And even then you are in trouble. In reality skydivers have given up trying to deal with this possibility in order to have small canopies with almost main like flaring power in the top of their containers.

Are we sure about that?

There are AAD fires for unconscious jumpers that land wingloadings in the range we're talking about, and are survivable. Even major injury free (limp bodies can sometimes pull that off). It's not ideal, and of course you're at the mercy of where you land, if its downwind, etc, and you go from a dusting to far more serious injuries quickly...

But what is the delta? Worth buying an LPV or na?

We're lacking a lot of data here. In the absence, we've made some assumptions. In some cases, those assumptions are discussed as if proven facts.

gowlerk

I have a hard copy of that. If I'm reading it correctly the average speed total velocity fully loaded is not to exceed 36 ft/sec with the brakes stowed. (24.5 mph) The descent speed is not to exceed 24 ft/sec. (16.4 mph)

I can see no spec for speed in full flight. Probably because there is none.

Full flight I wouldn't care as much about. Hopefully if if the toggles are popped it's because I'm conscious, and then I'm not as worried about landing a reserve.

It's my impact speed unconscious. Is that speed going to be similar between an optimum 160 and PDR 143, or a Optimum 143 and a PDR 126, etc. Or will more fabric mean a lower speed/lower kinetic energy.

If it's the same, I'll just buy a PDR.

I've heard this a few times: PD Optimums, despite being a size bigger, have roughly the same descent/forward speed as a a PDR one size smaller, negating most of the benefit of having a larger reserve for unconscious/no input landings.

Flight configuration would be brakes stowed, unconscious landing. People get low bulk reserves partly because the assumption is the landing speed (ground impact speed) would presumably be lower with the lower wing loading.

Example: A Optimum 160 would land about as hard as a PDR 143 (the next size down).

I've heard that from a few riggers, but I haven't seen any data to support that. I've got two rides on an Optimum 143, but of course I don't have anything to compare it to (or quantitative data).

Does anyone have any data to support or refute this? Is this one of the factesque things that gets widely reported and thus taken as fact?

Can someone from PD chime in?

"It's been widely report John, and that makes it fact-esque" -Stephen Colbert.

(Reposting this because initially I used the term "forward speed" to describe the kinetic energy effect on a human instead of "forward/descent" and the first two comments concentrated on that. I re-worded it to be more clear).

gowlerk

I can't really answer that question. But I can make a relevant comment. It's not so much the forward speed, but the total speed that matters. That is to say the downward speed plus the forward speed is the total speed you are moving. And that speed is different with the brakes stowed versus unstowed.

Probably the only people who can answer the question are the people who did the testing. And I'm guessing they will not say.

I should have been more specific, but yeah I mean forward/descent speed. Impact speed, essentially.

I'd be willing to hook one of each up for a test jump.

I've heard this a few times: PD Optimums, despite being a size bigger, have roughly the same forward speed as a a PDR one size smaller, negating most of the benefit of having a larger reserve for unconscious/no input landings.

Example: A Optimum 160 would land about as hard as a PDR 143 (the next size down).

I've heard that from a few riggers, but I haven't seen any data to support that. I've got two rides on an Optimum 143, but of course I don't have anything to compare it to (or quantitative data).

Does anyone have any data to support or refute this? Is this one of the factesque things that gets widely reported and thus taken as fact?

Can someone from PD chime in?

"It's been widely report John, and that makes it fact-esque" -Stephen Colbert.

dpreguy

Jumped a Safire from the factory guys at a boogie. It was a good canopy, but...since you asked.. The main difference between the PD products I also test jumped at the boogie was the length of the flare stroke. With the Safire (can't remember if it was a 2 or 3) I found I had to push the toggles almost down to my knees to get the same flare I got from a PD product by pushing the toggles to my waist. I jump a Stilleto 170.

I guess you'd get used to the longer flare stroke, but going from what I would call a "standard" flare stroke to the much longer Safire stroke was a surprise to me. Jumped the Sabre 2 there too and found the flare stroke to be of "normal" length, and quite nice. Ok, one jump. I get it. But I rejected the Safire because of the unusually long flare stroke. That's just me. Have jumped the Aerodyne Pilot and found the stroke to be also "normal" (to the waist) too.

One observer, one jump, one opinion here. Best to jump loaners and see if you agree and are happy with the product you will eventually buy.

I've found that Safires (2s and 3s) and Pilots are susceptible to too-long brake lines. If your brake lines are even an inch too long, you'll miss out on about 30% of the flare on the bottom end. Where as a Sabre 2 or Crossfire has more power evenly throughout, so if the brake lines are too long it doesn't affect the bottom end as much.

At least that's what I've found.

alexey

Avalon switched to Pin-type MARD (LES\Boost\Ace...)

Looking at fresh Avalon dom 09.17 now.

What's LES?

I was going by their website, which still mentions Skyhook.

Pobrause

As Austro Control is regulated by/ a national Department of EASA it IS tso‘d under EASA and therefore tso‘d under TSO c-23 f in any sense of the word and SIFE confirmed this to me.

At least that‘s my understanding of a conversation with the manufacturer. Attached one of their replies in german, can‘t find the mail where Diana mentioned the EASA part atm.

I confirmed with Sife, they do not have a USA TSO certification. It cannot be jumped legally in the US by US citizens, though foreign visitors may be able to jump it (though I think the reserve needs to be packed/sealed by a FAA certified rigger)

Soule76

Looking at getting a new (or new to me) canopy.
Pretty set on a crossfire.
I figure with the new crossfire 3 coming out there will be few crossfire 2's hitting the used market soon. Is the Crossfire 3's performance that much better than 2's that it justifies paying full for a new wing?

I'm not a swooper, nor looking to get into that for a while if ever. I just want something that is fun to fly. I have no problem paying full price for a new wing, but if I can get pretty much the same thing used and have a dozen or so lift tickets for the same price I'd just as soon go for that.

So basically, is the crossfire 3 better than the crossfire 2 and how?

Thanks in advance for any input.

I've got both. I have a Crossfire 2 129 loaded at about 1.4, and a Crossfire 3 109 loaded at about 1.7.

The Crossfire 3 is pretty different than the 2. Probably the most notable difference is it is trimmed steeper. The Crossfire 2 is trimmed flat, which means it will get you back from a fairly long spot. Not as flat as a Pilot, but pretty close.

The Crossfire 3 is trimmed more nose-down. The recovery arc is longer than the Crossfire 2, so you'll lose more altitude in a turn. I have to start my pattern higher with the 3 than the 2.

The Crossfire 3 also opens quicker than the 2. Not fast, but quicker. The Crossfire 2 has probably the softest opening of any canopy I've jumped. The Crossfire 3 is still quite comfortable, but the deceleration is a bit more.

They're both fun canopies, but fairly different. Crossfire 3 = more aggressive. Crossfire 2, not as aggressive. Though both are more aggressive than say, a Sabre 2 at the same wing loading.

Deyan

***As Austro Control is regulated by/ a national Department of EASA it IS tso‘d under EASA and therefore tso‘d under TSO c-23 f in any sense of the word and SIFE confirmed this to me.

At least that‘s my understanding of a conversation with the manufacturer. Attached one of their replies in german, can‘t find the mail where Diana mentioned the EASA part atm.

EASA doesn't regulate the manufacturing of sport parachutes since 2006. I don't care what the manufacturer claims. They do not have an FAA or EASA TSO. Based on the EU law, if it's approved in one of the EU countries, the rest should allowed it too. That's the loophole they are using. Funny times ahead with the Brexit. It can happen that since TS only have the UK approval, some EU countries might ban their products once UK leave the union....

Does Thomas Sport have an FAA TSO?

Pobrause

As Austro Control is regulated by/ a national Department of EASA it IS tso‘d under EASA and therefore tso‘d under TSO c-23 f in any sense of the word and SIFE confirmed this to me.

At least that‘s my understanding of a conversation with the manufacturer. Attached one of their replies in german, can‘t find the mail where Diana mentioned the EASA part atm.

TSO is a US FAA standard, though other countries adopt its methodologies. It doesn’t look like Sife has a TSO approval from the US FAA (or at least it’s realllly not clear), which would mean you can’t jump it in the us unless you’re a non-US visitor.

Deyan

*** or the non-US location makes the patent invalid or unlikely/difficult to enforce.

^^ This ^^

Speaking of non-US manufacturers, there's a company (Avalon) out of Bulgaria that does license the SkyHook (no TSO I believe). That's the 5th SkyHook equipped manufacturer that I know about in the sport market.

* UPT (designer)
* Aerodyne
* Sunpath Javelin
* Vortex
* Avalon

Deyan

******None of the other MARDs (RAX/ACE/Boost) have Collins Lanyards.

That's not true. There are at least 2 manufacturers that have a pin-based MARD with Collins lanyards. Sife and SWS.


Maybe what he meant to say is :" Non of the other MARDs on TSO certified rigs..."

Actually, I was unaware that they had colins lanyards. My understanding is it was a patented thing (I could easily be wrong there), and UPT wouldn't license it without the SkyHook. That understanding is either incorrect, or the non-US location makes the patent invalid or unlikely/difficult to enforce.