PDA Navigation

One of the most common questions from pilots that have recently completed their Cross Country Endorsements is “how do I create a PDA navigation setup?”. This page will cover:

  1. Airmanship
  2. Costs
  3. Equipment to buy
  4. Equipment to avoid
  5. Software
  6. Integration with club gliders (New 05/13)

The intention of this page is to demonstrate how to create a system which is glider independent and can be used in any glider. Additional considerations apply to self owned gliders where more integration is possible.

Update – 05/13 – As of Spring 2013, 296 and 96 have been fitted with FLARM units and connectivity for most common iPaqs, details of how to connect and iPaq to the FLARM is contained at the bottom of this document, the rest of this article remains largely unchanged.

Using a Navigation Unit

Using a Navigation Unit

1. Airmanship

A PDA setup can be a great aid to situational awareness if it is properly set up and you are comfortable with using it, but a few general rules should be followed whilst flying with one:

  1. Lookout! It is very easy to be heads down and focused on your PDA when you should be flying the glider. Become familiar with your PDA setup and monitor it with quick glances only. The proper place to learn your PDA is on the ground not at 3000 ft in a competition gaggle.
  2. Position awareness If your battery goes flat mid flight, you will need to get home without your PDA. Make sure that even if you are following a PDA track line, you have at all times at least one landmark in sight that you can easily find on the map and take your position from.
  3. Airspace & charts You should always be flying with an up-to-date 1:500,000 scale chart, this should be your primary airspace information source, you cannot rely on the airspace in your PDA being up to date.
  4. NOTAMs Be aware that your PDA will not show NOTAM warnings and temporary restricted airspace such as balloon launches and air displays by default. This can be added using NotamPlot (see below), but you must always check your NOTAMs
  5. Cables The most likely place for a portable PDA system to be mounted is on the canopy. If you need to bail out, any wires attached to the PDA may prevent canopy seperation and impede your exit if the cables snag on internal fitting’s. Any PDA system must have the minimum possible number of wires attaching it to the glider.

It is recommended that you make your first cross country flights without a PDA setup to ensure you learn to navigate without one. When your system battery fails at the wrong moment (and it will), you need to be comfortable going cross country using more traditional map and compass methods

 

2. Costs

With careful purchasing (including eBay), a decent system can be had for around £150-250 consisting of:

  • £65 for the mount
  • £40-90 for the PDA
  • £20-45 for the GPS receiver
  • £25 for an extended battery

These prices are approximate and assume a second hand PDA. Rememer that, other than the mount, most of the other items can be bought second hand and can be several years behind current models. For example, an Ipaq h2210 (a 2003 model) can run modern soaring software quite fast enough for our purposes and can be had for next to nothing on eBay.

3. Equipment to buy

Most people start by looking for a PDA they like the look of and then fit the system round this, resulting in some interesting compromises. A more sensible approach is to look at PDA, Battery and GPS availability together. If, like most glider pilots, this is going to be a single purpose system, a system bought for £150 using second hand gear and some clever eBay footwork is almost always just as good as a system bought for £400+ with the most up to date PDA possible when the same software is used.

PDA

The PDA itself is the most obvious item to be purchased, however it is actually one of the less important choices you can make. More important is the selection of extended battery and GPS unit, as these may restrict your options. Performance is generally not an issue for a single use system, any Windows Mobile PDA from the last decade should work absolutely fine (iPaq 3600 series onwards). Generally older models have better screens (the 3600 series allegedly having the best) as newer models look great in an office but are less suited to working under the glare of the sun in the typical cockpit.

Of greater importance is the card slots fitted. Ideally look for a model with both SD and Compact Flash slots (even if this means you need a CF expansion jacket). If you can’t find one suitable, an SD only model may suffice, however you will generally be limited to more expensive SDIO GPS units and will have to store all flight data on the PDA (with consequent risk of data loss should the battery go flat).

Cheap units commonly used include: iPaq 3600 – 3900 series, 2200 series (often the best combination of availability and price), hx2000 series

Extended Battery

The choice of battery is an important one as it will determine the longest length of flight that the system can be used for. Look for one with the highest possible capacity (at least 3000 mAh, which should give an endurance of around 6-7 hours at least). The availability of batteries with suitable capacities will limit your choice of PDA significantly, especially for older models, so it is often worth finding a battery first and then finding a PDA to match. Sites dealing in refurbished and unbranded accessories such as http://www.ipaqrepair.co.uk/ and eBay are a great source for this.

Be aware that some of the larger batteries will extend outside the casing of the PDA (and so have their own backing plate) so you may not be able to use mounts designed for the specific model of PDA you buy.

Mount

The mount is one area that shouldn’t be skimped upon. In flight loads will soon highlight if a mount is unsuitable, however the first thing you will know of it is when the whole unit falls into your lap when in the middle of a thermal! For a portable system suction mounting is the only realistic option, however there are suction mounts then there are suction mounts; RAM make some of the toughest mounts around and any mount you buy is likely to last well into the next millenium!

The main UK distributor is http://www.ram-mount.co.uk/ and the following part list will produce a generic PDA mount which will be more than sufficient to attach to any of the club gliders.

  • RAM-HOL-PD2 – Universal Three Finger PDA Holder
  • RAM-B-224-1 – Twist Lock Suction Mount with 1″ Ball
  • RAM-B-201 – Double Socket Arm for 1″ Ball
  • RAM-B-238 – Diamond Base with 1″ Ball

Don’t even think about trying a cheap gooseneck mount. Get a proper one and it will last forever.

GPS

Without a reliable GPS unit, the whole exercise becomes a little pointless so finding one that works well is essential. If you’ve followed the advice given up to this point, you’ll be looking for a CF GPS. If not and you are looking for an SDIO unit, the same considerations apply, just the end result will cost more. Consumer grade GPS units are easily available from eBay and a whole raft of tech stores, but with pricing ranging from £10 to around £300 or more it pays to be choosy. Beware of the lowest end units, they tend to require external aerial attached by long chords which are not practical for truly portable units. Ideally you want one with a built in aerial on top (as per the picture) although there is no need to venture much above £30 -45 to get a perfectly acceptable unit. If choosing between a number of units, look for low power and fast satalite acquisition.

When you first fly with a new GPS unit, see if it looses signal when you turn. Most units will get confused occasionally in a well banked thermalling turn, but if it is loosing signal regularly then it may not be a keeper. Unfortunately there are so many units it is impossible to review them all, but as a general rule, avoid cheap units which rely on a hinged GPS receiver, these have caused the most trouble amongst the (admittedly small number of) club members much more often than those with solid receivers.

As an alternative, if considering a full portable logging solution, GPS can be supplied by a logger such as an EW Micro, but this introduces more cable hazards and should only be considered if IGC logging is a primary requirement.

Update – 05/13 – Both icGC single seaters now have FLARM connectivity for iPaqs (details at the bottom of the page), therefore a standalone GPS is no longer an absolute requirement, provided your PDA accepts serial input through the chargin port on the bottom (most PDAs except the iPaq 1900 series), however one is still recommended as backup and for use in non-club gliders.

4. Equipment to avoid

Over the years, many people in the club have tried new ways of putting together a PDA system, either at a lower cost or for performance reasons. Some have worked, some haven’t. This list gives some of the ways that people have tried to approach this that haven’t worked, either because the setup is excessively fiddly or the equipment just wasn’t up to the job.

Cheap car PDA mounts

One of the most common bits of thrown away equipment is cheap goose neck car holders (illustrated left). These rarely have the strength to hold their shape during sustained thermalling or dolphining and tend so sag uncontrollably into your lap every time you pull on the stick. It really isn’t worth economising on the stand as this is the only thing that will ensure that the PDA stays put in more “enthusiastic” maneuvering. A loose, heavy, object in the cockpit resting on your stick arm is the last thing you want whilst trying to navigate a thermal.

Go with a proper mount and you will probably never have to change it.

External batteries

As an alternative to the sometimes hard to find extended batteries, external batteries, usually attached to the regular charging slot on the PDA, offer a tempting alternative to the problem of power as they are generally device independent. There are three main issues with this, firstly they introduce another wire from the canopy into the cockpit with the potential for canopy snags on a bailout as mentioned before. Secondly they take up valuable space in the side pockets which would be better used for water and thirdly (and most practically important), it is incredibly easy to knock out the plug in flight and not only loose power to the PDA but also to damage the connector on the PDA and render the whole unit unusable (as you can’t charge it!).

Smartphones

No matter how cool you think your iPhone or Android device (or whaterver smartphone you pick) is, and no matter how good it may look on the ground when running navigation software, modern devices do not have good daylight readable screeens nor the battery life to cover all but the shortest flights. And if it runs out of battery in flight, you are going to be in a bit of a pickle if you land out!

For comparison, under flight conditions, even if the mount can be found and the software loaded, without external power the average lifespan of a smartphone flight computer is about 2 hours, whereas the flight may last for 5 hours and the average 3000+mAh battery on a PDA will last 7+. External batteries are generally a no-no for the reasons listed above.

Bluetooth GPS

These are generally purchase with the intention of mounting them somewhere with a better view of the sky, such as on the top of the instrument panel. The key problems with these items are their limited battery life, the necessity for constant fiddling when signal is interrupted and the fact that when you least expect it, they tend to fall off their position and into the rudder pedals! Best described by one owner as “an expensive pain in the arse”.

Also consider the implications of power drain on the main PDA, there’s nothing more frustrating than loosing your PDA to power problems just before a marginal final glide!

Software

Once you have all your hardware set up, it’s time to choose the software you are going to use. There are a number of different options, ranging from open source (free to use) to packages that will set you back several hundred pounds.

Some of the more commonly used packages are:

  • XCSoar (www.xcsoar.org) – Free and open source
  • Winpilot (www.winpilot.com) – Two different versions, ADV @ $99 and PRO@ $125
  • SeeYou Mobile (www.seeyou.ws) – €236
  • Glide Navigator II (www.cumulus-soaring.com/gn.htm) – $95
  • Pocket StrePla (www.strepla.de) – €199

Most of these packages offer, to all intents and purposes, basically the same set of functionality so, unless you need a package which you can integrate into the glide computer in your own glider, a free package such as XCSoar should be absolutely fine.

When downloading your software, remember to obtain the following files:

  • Airspace
  • Maps
  • Waypoints

If you can, place all your files plus the installer for your software on a memory card in your PDA. XCSoar is capable of installing from SD card, so placing all files on the PDA will prevent you having to connect to the PC should the battery go flat and the PDA reset itself (again, something that will happen with depressing frequency).

Connecting to icGC single seater FLARMs

New 05/13
Both 296 and 96 are now fitted with connectors for most common iPaq models including:

h1910, h1915, h1920, h1930, h1935, h1937, h1945, h2200, h2210, h2215, h3800, h3900, h4150, h4155, h4300, h4350, h4355, h5100, h5155, h5400, h5450, h5455, h5500, h5550, h5555, h6315, h6340, h6365, hw6510, hw6515, hx2000, hx2100, hx2400, hx2700, hx4700, hx4705

These are connected to the FLARMs and will provide an NMEA GPS feed and 5V power to any compatible PDA. You will still need a PDA with a suitable suction mount to attach it to the canopy.

In order to set up a connection, please use the following settings in your chosen navigation program:

  • Com Port: COM1 (on most iPaq models)
  • Device Type: NMEAout or FLARM (depending on software, although it is confirmed that NMEAout works with XCSoar)
  • Baud Rate: 19200