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I fly a small airplane over the Rocky Mountains and carry a handheld 2M band transceiver with the idea that it might help me get rescued in an emergency landing situation. We have pretty comprehensive repeater coverage around the area, which is monitored for such purposes pretty much continuously. However, I'm very aware that the rubber duck antenna is not going to provide the best performance. Of course, an antenna intended for a potential emergency situation must compromise considerations other than mere ERP, not least it mustn't poke me in the eye while I'm flying (and the conventional wisdom is that if you make a forced landing in an airplane, anything that you're not wearing / carrying on your person at the time must be considered non-essential to survival).

At this point, I'm considering the "signal stick" on the belief that I could carry it coiled into a circle Signal stick antenna. I'm also pondering whether I might make something with a modest length of co-ax attached such that I could somehow throw it up into a suitable tree to get more altitude.

In pursuit of this improvement, I'm looking for a) considerations that I might have overlooked, b) any experiences that folks can offer regarding how effective any such options might be in practice, and c) recommended references where I can do some study regarding this topic. Preferably such references might be prioritized, I'm painfully aware that one could (and probably some do) spend a lifetime (or at least a PhD-time) researching antenna topics.

TIA

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The signal stick antenna looks like a pretty good choice. Any full length 1/4 wave antenna should be fine. Check reviews for mechanical strength etc.

The 7 or 8 inch antennas that come with handheld radios are a compromise for portability. I did some measurements on one and its efficiency was about 25% or -6 dB. This also assumes it's perfectly tuned, being short it has a narrow bandwidth so might be worse at your particular frequency.

You can improve the efficiency it a bit by installing a "tiger tail" counterpoise, which is another 0.5 metre wire that hangs down from the radio connector or chassis. This helps because the radio otherwise has to use your hand as the counterpoise, and it isn't all that conductive. Search the internet for various ways to connect it - to the antenna ground, to another screw on the housing, or even the power connector. In fact the charging cable might work fine, if you roll up the excess tightly, at the far end so it's about 0.5 m from the base of the whip.

I have a roll-up MFJ J-pole for portable use, it can be tied to a tree or a stick, handy because it can be higher up and removes you a bit from the antenna. I've never actually measured its performance though, and I have a low opinion of J-poles in general as their patterns aren't always well-controlled. Good VSWR doesn't help if the signal is all going up at 45 degrees from the horizon.

For serious emergencies I also seriously recommend an EPIRB, which transmits directly to GEO and Gnss satellites. This is the correct solution for being rescued from the wild, it's compact, accurate, reliable, works with little effort and has a 10-year battery shelf life.

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    $\begingroup$ The EPIRB advise is good in general, but I would think any aircraft would have an ELT device like that required already: aopa.org/advocacy/aircraft/aircraft-operations/… (The older 121.5/243 MHz ELTs merely sent out a beacon signal when activated, whereas iiuc the new 406 MHz ones are basically EPIRBs by a different name…) $\endgroup$
    – natevw - AF7TB
    Oct 24, 2022 at 18:45
  • $\begingroup$ Ah, I didn't know it was mandated even on small planes. I'm always suggesting them for hiking and so on. Of course boats and aircraft have them. Thanks. $\endgroup$
    – tomnexus
    Oct 24, 2022 at 21:30
  • $\begingroup$ My friends in the local CAP (responsible for search and rescue operations here) have advised me those options are by no means infallible in our terrain. Since I already own the HT, it seems a small, easy (essentially free, subscription-free, and also "amusing") step to add it to the resources. $\endgroup$
    – Toby Eggitt
    Oct 25, 2022 at 23:05
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If you're into DIY, a J-pole antenna made out of twin lead or speaker wire might have more gain than a ducky antenna, maybe even more than a quarter wave with no ground plane. Wads up to fit inside a pocket. Maybe add some string on the end to make it easier to throw up into a tree.

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  • $\begingroup$ That would be an interesting project, and of course easy enough to try it out in the safety of not having crashed :) $\endgroup$
    – Toby Eggitt
    Oct 26, 2022 at 4:21

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