How to Practice an Avalanche Transceiver Search & Rescue
- Henry
- 3 days ago
- 5 min read
Updated: 2 days ago
Ask yourself this: how often have you practiced putting your avalanche probe together? Digging with your avalanche shovel? Do you know how far the actual range on your transceiver is?
This is where spending some time, either before your trip or when in the mountains before heading off on you’re your holiday.
Practicing a Transceiver Search
It was a surprisingly warm January afternoon when my friends and I gather in Hyde Park for some pre-trip transceiver training. The aim was simple; get familiar with the stages of an avalanche rescue search, then walk through some of the steps to get familiar with using the equipment (almost) in the field.
First was a walk-through of the transceiver search process, with one or a pair of transceivers placed in a (pair of) backpack around 100m away. This looks a little something like the following:
Whilst the avalanche is in progress, pay careful attention to see if anyone is caught and carried – if they are, keep careful tabs of them
Immediately ski down to the lowest point at which you saw the person/people caught, carried and buried. Remember to ski safely at this time so you don’t trigger another slide – the path of the first avalanche will always be safe, as slopes that have slid will not slide again until reloaded with fresh snow.
At this lowest point, whip out transceivers. Set all of the transceivers in the party to “search”, so that transceivers not in use do not impact the searching
Begin a broad search
If you are by yourself, ski in broad traverses back and forth across the slope, dropping down by no more than 20m between each traverse
If in a team of two or more, split apart by up to 25m (and not wider than the footprint of the avalanche) and quickly but calmly work your way down the face of the avalanche, maintaining this distance
As you work your way over the debris, begin calling out key information such as “signal found” when your unit picks up a signal, and counting down the range in major steps such as 5 or 10m increments
When the range drops to 10m, begin a coarse search, following the arrow carefully.
When the transceiver gets to around 3m, begin the fine search – detach from skis (maybe not wearing them if you’re in a park!) and follow the range count to the smallest number; this will involve crawling on your hands and knees, then holding the transceiver right against the snow and moving it in a grid to establish the lowest number.
Here the transceiver search is complete, so restart the process and this time walk-through without stopping to read instructions.
Learning Points
The aim of this exercise is to demonstrate a couple of really interesting things when using transceivers, nuances with how the design of modern 3-antenna digital transceivers work.
First of all, pay careful attention to what distance your transceiver picks up the first signal. Most transceivers will first pick up a signal between 40 and 60m away from the target. It is often useful if you run the scenario with a unit running on low batteries, to see how this can affect the range. The latest batch of units will regularly run up to a 60m range.
Second, notice the shape of the path the transceiver’s arrows send you on. This is a direct fluke of the nature of radio waves, which are curved, and the layout of the three antenna in modern transceivers. You will find that the arrow sends you in a noticeable curve towards your target; don’t be surprised if you find yourself being led at a 60° angle away from your target when the signal is first acquired. Keep going, keep following the signal, and it will bring you round in a “rugby ball” shaped path to your target (something very similar to an American football, for any US-based readers). This is completely normal, but being familiar with it is one of the biggest takeaways of doing an exercise like this.
Finally, the fine search. This is often the slowest and most frustrating part of any search, simulated or in real life, for a couple of good reasons. Transceivers take a couple of seconds to update their position, so you can’t simply swing it back and forth over the search area; instead, you need to gradually move it back and forth, left and right over your imaginary grid, waiting for the numbers (there won’t be an arrow at this point) to catch up with themselves.
These are three really important lessons that you don’t want to be learning for the first time out in the mountains, when your friend’s or family member’s life is at stake. So grab your ski buddies, find a park, grab a coffee (or a beer, who am I to judge?) and learn what a transceiver search looks like in real life.
One last trick to play; place a transceiver in search mode, and stand around 1.5m away from another switch on unit, so you have the searching transceiver pinging in fine search mode. Let it establish its range, then take a mobile phone and place it against the searching unit, playing careful attention to what happens to the range; it will jump around all over the place, maybe settling on a range that is just, well, wrong.
This is a really key lesson about how to carry a transceiver both when travelling around the mountain, and when searching. When travelling around the mountain, carry your transceiver in opposite “corners” to your phone and other electronics – if your phone is in your left-hand chest pocket, keep your transceiver in your right leg pocket, or vice versa. And when searching, hold the transceiver level in front of you, as if you are a waiter carrying a big, round tray of food or glasses.
Probing and Shovelling
I wish there was something as easy to practice shovelling and probing. Unfortunately, unless you have dedicated time to bury a backpack (or a friend) in the mountains, then this is not easy.
The two points on this I would make are; learn how to deploy a probe properly – by throwing the pieces out across the ground in front of you, then pulling hard on the pull cord at the top – and understand the most efficient points of shovelling.
For this latter part, remember the following. Shovelling is really, really hard work, so if there are two or more of you arrange yourself in a system, with one person at the “coal face” shovelling for their lives, with the other just behind them moving the shovelled snow out of the way. Anyone else involved can rest of chip in where they can. As soon as 60 seconds has past, the second person grabs the first and removes them from the “coal face” and takes their place; this is exactly the system used in CPR, so is a good way of remembering what to do.
Finally, shovel in to the hill, not down: once you’ve established the depth of the victim, come downhill by that same amount, and dig into the side of the hill – it is a helluva lot easier than trying to dig down, and significantly easier to move debris out of the way.
