yuri_base

To reiterate this point: *of course*, in light winds and for experienced jumpers/groups, it would be ridiculous if somebody was standing in the door staring at their shoe. The 6s separation for solo belly and up for bigger groups, is simple enough to feel intuitively, 6 seconds is a time interval that is naturally consumed by pre-exit activities such as looking at the jumper exiting before you, waiting a bit and taking your position in the door. As long as you don't rush, 6s passes just like that. But in strong winds, this internal feel of timing fails. If the uppers are 80mph and the 100mph plane now travels at 20mph ground speed, the separation time must be increased 5x! So, it must be 30 seconds for solo belly and something like a minute for small groups, etc. Now, I've never ever actually seen somebody waiting for 30s, let alone a minute on windy days. Yes, jumpers more or less understand that they need to wait more, but a few realize how dramatic the increase must be. In such situations, SEX (naturally, an abbreviation for Shoe EXit separation method ) gives a solid tool to insure proper separation. And you get the time and justification to stare at your shoe as long as needed. But besides this, SEX can be a rule of thumb (or rule of shoe) for students and low-experience jumpers. One of the first posts in this thread was, Jumpers WANT rules of thumb. 45 degree rule is dead, something should be invented to replace it. SEX is the answer. Easy, always available, and automagically works in any wind. Shoes... shoes everywhere! It was the clown shoes that instigated the Wingsuit Theory. 10 years later, they help jumpers avoid collisions. It's magic, pure fucking magic! [inline ShoesEverywhere.jpg] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

To clarify, by "flying away" I meant under canopy, not tracking. And yes, extra separation should always be given to groups, the bigger the more - at least, by typical radius of their "track umbrella". Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

So, I was thinking, would it be possible to have some easy to use visual aid in determining the exit separation that would automagically account for ground speed? And came up with this simple idea. We need to achieve a certain amount of separation over the ground, not the air, as was discussed to death in the previous over 9000 posts (the effect of the wind at opening altitude, let's face it, is relatively minor in this discussion; all jumpers should be flying away from the plane/current deployment area after opening anyway). Let's say, we need 1000ft (300m) over the ground. So, we simply wait until the plane travels 1000ft over the ground, because the trajectories of jumpers with the same terminal speed are translationally parallel to each other and thus are offset by the distance the plane covered over the ground; but how can we gauge this distance? Magic shoes to the rescue! Here's a photo from one of the recent articles on the front page: [inline LakeBalaton.jpg] Jumpers look down from the top of the door, and for a given exit altitude their shoes provide a certain scale on the ground. Here, the shoe width corresponds to about 1000ft on the ground, just what we need. [inline MagicShoe.jpg] (Indeed, if the exit altitude is about 13500ft, 1000ft on the ground is 1/13.5th of it, which is the same proportion as a 11cm-wide shoe as viewed from 1.5m (5ft) height. So, when the previous jumper exits, you stick your magic shoe like on the pic, hold your head steady near the top of the door (e.g. lean it against your hands holding the handlebar) and notice a feature on the ground on the forward side of the shoe. Wait until this feature emerges on the aft side of the shoe. That's it, you have about 1000ft/300m of separation, you're good to go! What if you're a student and there is a freeflyer exiting before you? For a belly jumper (120mph terminal speed) exiting the aircraft flying at airspeed 100mph, the forward throw is about 1300ft; for a headdown at 180mph terminal speed, the throw is about 2000ft, as can be easily calculated in Wingsuit Studio: [inline ExitSeparation.png] So, you need extra 700ft of exit separation, so you need to wait almost double the width of the shoe. Or, instead of using a shoe for reference, more permanent solution is to tape some bright markers to the doorstep at appropriate distance. Here you go, a simple and visual method for exit separation that automagically accounts for ground speed. Of course, for experienced jumpers it's should [usually] be enough to just rely on the sense of ground speed and time and use their experience, or use a separation chart, but this method can be a good educational tool for students as it emphasizes the importance of ground speed, amount of separation, various amounts of throw for different types of jumping, and gives them an easy tool to gauge the separation, the tool they always have on them. The shoes. It's magic, pure fucking magic! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

"One more thing..." Rockdrop Pro also uses Wingsuit Equations, so the celebration wouldn't be complete without this child of WSE. So, Rockdrop Pro app will also be free on December 7th. Download Rockdrop Pro here: Android+Wear ~ iOS ~ Windows However, for Android users it will require a bit of work: unfortunately, it's not possible to make a paid app on Play Store temporarily free; free is permanent. So, you'll need to use a promo code. I've generated 357 promo codes (out of 500 allowed for the quarter) - remember, 3.57 is a magical L/D, thus, 357 codes. The list of promo codes is attached. If one doesn't work on December 7th, it means it was taken already, try a different one. The other children of WSE - L/D Vario (Android+Wear ~ iOS ~ Windows), Wingsuit FAP (Android ~ iOS ~ Windows), and Wingsuit Studio (Win 32) - are already free. Flying smart is the new cool, so join the party!!!

To celebrate the upcoming 10th Anniversary of Wingsuit Equations - [inline WSE.png] [inline 10th.jpg] - L/D Magic and all of its optional components will be free on December 7, 2016. Get your piece of Pure Fucking Magic while supplies last! Download -----> [inline LDMagic.png] L/D Magic now supports 10Hz sample rate with Bad Elf GPS Pro and Dual XGPS160, as well as 5Hz with Dual XGPS150A and Emprum UltiMate GPS. The app is iPhone-only. For Android and Windows phones, I have a simplified app called L/D Vario, see this thread. Note that while L/D Magic has two modes of operation - one with the phone mounted on a vane in free stream, using accelerometer to measure L/D, and the other with the phone in pocket, using high-speed external GPS; L/D Vario works only on a vane. Here's an example with LG G Watch R: https://www.youtube.com/watch?v=u_iPSSV-5qY (Also, a fast built-in pressure sensor is highly desirable to get accurate measurements of the polar curve speeds. LGGWR has one at 90Hz; the champion as of now is Nixon the Mission smartwatch with 165Hz sample rate reported by a user.) Another difference between L/D Vario and Magic is that the former does not require exit at exact moment of "c-ya!" count like the latter; it works continuously. L/D Magic requires precise start because it needs a start point to integrate WSE and run Kalman filter; thus it's more suited for BASE as it's hard to exit at exact moment from the airplane. Vane: you need to make one yourself for your device. It needs to be balanced neutrally on its axis and mounted on a pole at least ~2ft from the belly (helmet is not a good place for this) so that the angle of the relative wind hitting the vane is the same as the angle of your velocity relative to the air mass (i.e. the vane is in true free, undisturbed stream). Like this: [inline Vane.jpg] Any questions about the use, feel free to ask here or by email in my profile. WSE are an azaming (i.e. so amazing that can't even spell right) phenomenon - they're so simple to derive that it's like kicking a rock with your foot and boom! it splits in half and a 100-karat diamond rolls out of it! And in 10 years, I derived so much useful stuff from it that it fills several Moleskins with yet unpublished gems waiting their time: [inline Moleskins.jpg] And it shows no signs of depletion. For example, recently I found a more accurate estimate of the L/D necessary to achieve maximum sustained horizontal speed: 1.3 for wingsuits capable of max L/D of ~3.0 (the previous result from 10 years ago was square root of 2; it turns out this is for infinitely high L/D) - useful for those participating in speed competitions. The recent idea of FAP (Fast, Accelerated Proximity) was also fueled by WSE. It almost feels spiritual: it can't be so simple, so beautiful, so powerful... but it is! I don't know if there's God or we're living in a computer simulation run by another civilization, but to me WSE ring that tiny bell that it's all not random... all these big walls, diving boards as if specifically made for BASE... there must be The Old Dude in White Wingsuit Sitting on a Cloud watching for us! Beeeeeeeeeeeeeeeeeeeeeeeeeeer and azaming flights, everyone!!! Yuri Base Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> You people are dense, and Yuri just wants to sell his product. My products are free, except for some advanced features in L/D Magic only a handful of people in the world would buy. What I truly want is to better understand human flight, have fun applying physics anywhere I can apply it (afterall, my PhD in Physics can be used for betterment of humanity , as my current profession - programmer - does not involve any physics), and - hopefully, but in reality mostly hopeless - let people know that while they are free to cling to the past, to the era of horses, candles, fire stoves, and abacus, and live in denial... the future is here and it's ok to live in the era of fast cars, jetliners, electricity, and computers that fit on your wrist. It's ok to wake up. [inline WakeUp.jpg] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> You're trying to apply theories developed for fixed wing, constant velocity, and highly streamlined aerodynamics (which do work to a limited degree), wingsuits are none of those (sometimes constant velocity but rarely). You also have no data on the wing shape, it would be like taking flight data from an airliner and not knowing what the flaps or slats were set at (or that they even had flaps or slats) and trying to infer it's flight envelope. The Wingsuit Theory is developed using only two fundamental laws of physics: 2nd Newton's law (F=ma) and proportionality of the aerodynamic force at high Reynolds numbers and subsonic speeds to the square of airspeed (F ~ V^2). That's it. It applies to any wing shape, dihedral, AoA, fully stretched or collapsed wings, flaps, slats - anything. Any dynamic changes in flight configuration - AoA, shape, surface area, wing profile, trim, etc. - are encapsulated in "magic" coefficients of lift and drag Kl and Kd which can be measured by the tools I created based on WST. Velocity does not need to be constant - constant velocity is simply a point on a polar curve that can be used in Wingsuit Equations to calculate any dynamic situation. (see Wingsuit Studio) Of course, for acrobatics this won't be applicable (because for flips and barrel rolls the rotational dynamics needs to be taken into account), but for any normal flying it works. It even works for no-lift freefall (belly, headdown, sit) - it's just Kl=0 for these, that's all, WSE still work. So, unless the XRW participants are trying to win the Darwin Prize: [inline DarwinPrizeXRW.jpg] - it's better to be smooth and make only slow adjustments, in which case WST works like a fine swiss watch. > If you really quantified a wingsuit's performance with all of its variable geometry you would end up with dozens of curves that would have to be compiled to produce something useable. Exactly. One way of doing this would be to gather all polar points in one spreadsheet and plot them all on the same chart using a circle of low opacity (1%) with radius representing error margin for each data point, with sustained horizontal and vertical speeds adjusted to sea level to eliminate the effects of variable air density. After a lot of jumps in various flight configurations in the same suit, points will be ending up on top of each other, making opaque regions that will be more defined the more time was spent in these flight modes. A shape in polar space will be formed (with somewhat fuzzy edges due to measurement errors) which is what we're looking for - wingsuit's polar region/envelope. > You aren't producing anything more comprehensive than what someone with a FlySight could tell you after a few jumps and very little data analysis. Flysight is just a GPS and thus wind is blended in the data and cannot be reliably removed. Also, current (momentary) speeds are not easily translated into sustained (polar curve) speeds. One needs to fly at really, really constant speeds for prolonged periods of time - and subtract wind accurately, or fly in true zero wind - to claim that these speeds represent a point on a polar curve. It is quite common that people slowly bleed horizontal speed (most of the time, subconciously) to get better dynamic glide. L/D Vario and L/D Magic, when used with a vane, are completely independent of the wind, and calculate sustained horizontal and vertical airspeeds for every moment, even if current speeds are changing. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> A jumper that has just exited is in the same air mass as the aircraft, and their trajectory will look exactly the same in 0 wind, 100 mph headwind, 100 mph tailwind (even if they *do* reach 45 degrees at some point). The necessity to compensate for the wind has been discussed in so many posts and articles - "over 9000" - that I didn't mention it on purpose. I'm making a point that haven't seen mentioned before. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Using a clinometer app in the mountains, I had a chance to see on many occasions how poor our (ok, at least mine) eyes are as protractors. I tend to overestimate angles by ~8 degrees on average. What seems to be 45 degrees, is actually 37. Now, tan(37) = 0.75, so for 120mph terminal it corresponds to 90mph jumprun airspeed, which is about average. So while I'm not advocating the 45 degree "rule", never used it and never heard anyone mentioning it (except, if vague memory is correct, during AFF), I can see how it came to existence - it DOES look like 45 degrees, even if the exact measurement is 37. I think using a precise instrument (camera mounted at 45 degrees) to say "look, it's not 45 degrees!" - [inline 45.jpg] - is not a valid experiment when dealing with such an imprecise instrument as human eye protractor. A more valid experiment would be to stand at the door and just ask multiple jumpers, "what do you THINK is the angle to that jumper/group?" Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> neither of these is a ridged wing glider, and a WS falls completely out of this analysis because a complete change occurs in drag, span, chord, camber, airfoil, angle of attack, and planform to attain each of those data points, and the same data point can be reached by several combinations of each. Yes, unlike rigid gliders, wingsuits have polar regions, not curves (the areas on the graph above are shaded to show this) due to variable geometry. However, every glider has an "envelope" (bright colored curves above) that it cannot go beyond. For wingsuits, this envelope is flying with fully stretched suit, but at different angles of attack. If wingsuit polar region does have an intersection with canopy polar curve, XRW is possible, and wingsuiter can fly in any flight mode along canopy's curve inside the WS region. If canopy and wingsuit manufacturers measured polar curves/envelopes for various canopies/sizes and wingsuits for average body build - "technical passports" like they have it for gliders - these curves don't need to be measured by users, they can be just scaled for different wingloadings to find the intersection. Unfortunately, we've never seen any hard data from manufacturers and it's not likely to happen soon, but technically-minded enthusiasts can build their curves using L/D Vario and L/D Magic. Here's an example of polar region of one jump (flying the swiss crack) - bright green on the bottom graph, ignore darker green as it's from Kalman filter catching up with data in the first few seconds after exit: [inline Sputnik_2013-08-15-2.png] Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> In short-is there common way to measure compatibility other than "so and so flew a X bird/C Race/ Whatever next to a VK/ Petra/Whatever with 43 lbs of lead and it worked so thats the standard..." This problem can be solved scientifically by measuring canopy's and wingsuit's polar curves and finding their intersection. To fly together, you need to have exact same horizontal and vertical sustained speeds - i.e. both of you should fly at the same polar point. I wrote about somewhat similar thing here - two WS jumpers with vastly different wingloading flying together. [inline PhatVsSkinny.png] If there's no intersection, canopy's polar curve can be scaled to different belly belt weights to see if intersection is possible. So, it is possible to know in advance what to aim for instead of blind trial/error. Tools for measuring polar curve do exist. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Craig, that's awesome! I'm curious, what's the barometer sample rate on your Sony watch? Sony Z3 Duos phone has 30Hz. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Anybody with any LG smartphone with a barometer? It looks like manufacturers use the same pressure sensor across their lineups: all iPhones 0.8Hz, all Samsungs 5.6Hz, all Nexuses 30Hz... I wonder if LG uses the same 75Hz pressure sensor in their phones as in their watch? Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Note that LG G Watch R (and most likely, any other water-resistant smartwatch/smartphone) has a breathing hole with a membrane that delays changes in pressure. This effect can be easily observed just by touching the watch or pressing on its case: you see the pressure readings change and then return to equilibrium within several seconds. Before LG, I had a Samsung Gear S which was terrible in this regard. Even on a ride up it would lag a couple hundred feet. LG is not so bad and on the ride up was pretty much in sync with my other altimeters (Altimaster and Viso). In freefall I would expect a noticeable delay in altitude. I might disassembly my watch and see if I want to puncture the membrane or drill a small hole in the case. With Gear S, I used to take the SIM door off and then the response was instant. But then the sweat could easily get inside and destroy the circuits. (Gear S instantly died when I briefly submerged it in water (with the SIM door sealed, of course) - so much for IP67 rating.) Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> Can you make this watch so that, the watch only shows display of the altitude? Of course. This will be the very first version. > Can you zero it out to your landing area? Absolutely. > How fast does it refresh? Up to 6 frames per second for textual display and 30fps for graphic display (there will be option to choose different visualizers, just like in L/D Magic). For text, anything faster than 6fps makes the last digit blink too much. The barometer in LG G Watch R (and I presume, in Urbane) runs at 75Hz. The number crunching algorithms will run at full accelerometer speed (200Hz). Of course, if your device doesn't have a barometer (or it's slow) and only GPS, the update rate will be limited by its sampling rate. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Just checked the app on iOS 9... holy shit, Apple broke so many things! On 16:9 screen it shows the app as 3:2 3.5-inch app, with black bars on top and bottom. Trying to view Kalman Filter model descriptions or Help crashes the app. Fonts are messed up. It feels embarrassing, as the app appears sloppy and buggy, but I poured infinite hours in it (3 years in making!) sweating every fucking pixel, and it was bug-free. Sorry, folks, for the bad Apple. You can still download the app, but if you want to view Help and KF model descriptions, download the PDFs here: LDMagic_1_0_1_Help_English.zip I'll work extra hard to deliver the update ASAP. Stay tuned. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Yes, I use Xamarin for Android/Wear/iOS and Visual Studio for Windows. Visual Studio can also integrate Xamarin's Android/iOS (you still need a laptop with Xcode to build iOS apps), but for now I run Mac version of Xamarin and Visual Studio in Windows on VMware on a MacBook Pro. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

L/D Magic is now FREE!!! [inline AppleStore-EN.png] The price for the app is now moved to the optional Flight Data Recorder in-app purchase, so that more people can try the app and see if it works for them or not. It's a very complex app I wrote to fulfill my vision, it's not a plug-and-forget, but rather a serious scientific instrument. Examples of jumping with L/D Magic: 1. vimeo.com/132279770 2. vimeo.com/108428363 3. vimeo.com/108326309 It can be used EITHER on a pole/vane OR in pocket, but in latter case requires an external GPS for high quality signal and high sample rate. Currently, Dual XGPS150A (Bluetooth) and Emprum UltiMate GPS are supported at 5Hz. Other external units should work, too, but most likely only at 1Hz. As I shifted my programming attention to cross-platform development in C# (while L/D Magic was written in Objective-C), it hasn't been updated in a while, but the update is coming with iOS8+ support, compatibility with 10Hz sample rate for Dual XGPS160, bug fixes, etc. Any questions welcome. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Some news from the development front (may be of general interest for other devs): #1. Impossible is possible: every one of the 4 apps on each platform consists of just one line of code (C#): Shared.MainEngine.Instance.Initialize(some platform parameters).Start(); That is fucking it! All other lines of code - thousands of them - in main engine are absolutely platform-agnostic. Of course, the engine links to some libraries, some of them cross-platform (various math, physics, Wingsuit Equations, etc.), some are abstractions from the platform specifics (UI, sensors, sound, localization), but all these libraries are generic and can be used in other apps, so the relative effort of writing them approaches zero in the long run. #2. Localization (text, images, sounds) is also fully abstracted from platform specifics (all these horrible platform-specific ways of localization - *.xml, *.resx, *.strings - make me want to puke as you have to manually copy each string between platforms and escape the special characters), now all resources are in one folder which is simply copied between the 4 projects without any changes. Lovely! #3. The visual designs in each of the 4 projects consist of just one container in the window. That is fucking it! Custom crossplatform layout engine fills this container with all UI elements in such a way that you can't see screen differences between platforms by naked eye, only using bitmap difference in photoshop can reveal small differences caused by slightly different rendering of the same font by platforms - here's the diff between iPhone 5 and Note 4: [inline PlatformDiff-EN.png] Sweet! These are some invisible things behind the seemingly simple app with some numbers on screen. It's magic, pure fucking magic! Now I need me some well earned beers! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

> I bought a Dual GPS150, which is a small box like thingy that amplifies the GPS receiving capabilities of the tablet and makes it far more reliable and precise. Yes, I have XGPS150A and 160, which I use with L/D Magic for high sampling rate (5Hz and 10Hz) necessary for Kalman Filter. For most navigation apps that do not integrate Dual's proprietary code, the update rate will be 1Hz as usual. Frankly, I gave up working with Dual and Bad Elf developer support because it sucks. But I agree that these external units are beneficial even at 1Hz since they have better GPS chips than most phones/tablets and also they drain phone/tablet's battery less as Bluetooth is far more energy efficient than GPS. A must for long hikes as you don't want a dead phone. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Haha, I saw that 1Hz, too, for Band 2, was curious if I want to include it in my arsenal. Who knows, maybe internally it runs faster, just averages samples and feeds them at 1Hz only. Don't worry about the hardware, writing code is much more important. The hardware improves so fast, that by the time you write something you find out to your delight that the hardware became much more powerful and versatile. Software is hard, because you have to do every bit of it by yourself. Hardware is easy, because you don't have to do anything. For example, think about why LG put that 75Hz pressure sensor in their watch. They don't advertise this number, they don't even mention it in the specs. Why not 5Hz? Or 1Hz? My guess is that the manufacturers of these sensors improve their chips and retire old ones. The new ones are much better and cheap as dirt (literally - that sensor might cost just 5 cents in bulk). So an LG smartwatch designer looks at the chip catalog with thousands of different sensors and just picks something that fits their size, power, cost, etc. requirement. And it just happened to have 75Hz rate. In other words, we get better and better hardware not necessarily because market demands it, but because everything evolves and there are better components everywhere. Code, code, code! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Yes. (Though logging might be part of "Pro" feature package available as an in-app purchase.) For change/effect in wingsuiting, you need L/D Vario, because it measures L/D, not GR, and it's instant (~0.2s response time). It is a common misconception that observing changes in GR helps you find the sweet spot (max performance). This is because while L/D (your aerodynamic property) changes instantly with body position and AoA changes, glide ratio has an exponential response, which can take 10-20-30 seconds to stabilize and asymptotically approach sustained flight. So you need to detect a slight change in tone in 30 seconds from now - you need Mozart's ear for that. Most people using audible glide indicator mistake slow flare with improvement in L/D - they trade the forward speed to better glide ratio, which can last only limited time (although it can last up to a minute or so, depending on initial speed). When GR finally drops, they think that it's because they got tired or somehow else lost the sweet spot. Then they go do WS BASE using their muscle memory and... land in trees at linestretch trying to clear a ridge because they exhausted their forward speed without realizing it. Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

I would appreciate your input on barometer sampling rate in your device if it has one. How: download L/D Vario (free app, links above) and tap the "i" icon, you will see the info about sampling rates of accelerometer, barometer, and GPS: [inline Frequency.png] I'll start: LG G Watch R: A(ccelerometer)=200Hz, B(arometer)=75Hz, G(PS)=N/A Samsung Note 4: A=200Hz, B=5.6Hz, G=1Hz iPhone 5: A=104Hz, B=N/A, G=1Hz Lumia 520: A=80-90Hz, B=N/A, G=1Hz Your turn! Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio

Ever since I got an Android Wear smartwatch, LG G Watch R, which has an incredible pressure sensor with 75Hz sample rate and amazing always-on display, I wanted to have an altimeter on it with various useful features for skydive and BASE. Besides smartwatches, more new smartphones get barometric sensors. However, I haven't found any good app that would fit my needs, neither for smartwatches nor for smartphones, on any of the 3 app stores. After I wrote L/D Vario: [inline LDVario_v.2.0_EN.png] - an app for thinking wingsuiters that works on 4 platforms (Android+Wear/iPhone/Windows) - I want to use my advanced data analysis algorithms and cross-platform engine for something else useful. So, here we go... I'm going to write an app, Smart Altimeter, that will work on any device with a barometric sensor. The app will be free. (However, I don't exclude the possibility that some advanced, optional features could be purchased for a small fee - I want to eat drink beer, too, sometimes.) The main emphasis will be made not on traditional visual use in skydiving freefall (since today's screens are still quite poor in direct sun), but on things that smart devices can give to us that "dumb" altimeters can't - taptic and audible feedback, useful features on a ride to altitude in skydiving or mountain hike in BASE, data recording and analysis, and so on. I am all ears listening to your wishes. Let's go!

A trivial, yet easy to overlook bug in my custom localization engine caused the app crash on launch if system language was not one of the supported languages (English and Russian). Sorry, Frenchies, that you could not flyaii yer bodeé with my app! The updates are submitted to all 3 stores, however, while Android is already live, iPhone takes ~7+ days for approval (and submitting updates while the previous version is waiting for review resets the clock! what a shame, Apple), Windows ~2+ days. C'est la vie! Android+Wear iPhone Windows Android+Wear/iOS/Windows apps: L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP iOS only: L/D Magic Windows only: WS Studio