They were stored in a card box in dry conditions, since 2018.
Could be simply a crap product. There is no reason why flares should not have their share of junk.
Excellent video on ditching in different aircraft types, from the well known Barry Shiff
For a TB20 (low wing retractable) he recommends 8 deg up pitch.
Remember to loosen your tie 
I disposed of the two flares, in an incinerator, and standing well back
Remember that you are supposed to hold this in your hand!
disposed of the two flares, in an incinerator
Ah, that was you!
Tell you what… the light is totally blinding at 10m, so if activated handheld, you will not want to be rescued because nobody will want you afterwards because you will have no eyes and one arm
It was all over the news here. “Aurora borealis over England?”. I did a ditching course once and they let me light such a flare. Not a big deal really, just hold high and away from your body.
aart wrote:
It was all over the news here. “Aurora borealis over England?”. I did a ditching course once and they let me light such a flare. Not a big deal really, just hold high and away from your body.
Also my experience – we used up a lot of “out of date” flares when I was a kid – I didn’t realize how dangerous they were, but never more than a bit of a burn from the stuff falling off the flare – you quickly learned to hold it with your arm up at about 45 degrees to let the bits drop on the ground not on your arm.
Tell you what… the light is totally blinding at 10m, so if activated handheld, you will not want to be rescued because nobody will want you afterwards because you will have no eyes and one arm
You should come to Croatian football games to see what really big flares are. On several occasions fans torched good part of stands.
I used a handheld flare ~50 years ago, engine problem off the Caithness coast bringing a newly bought boat from Wick to Inverness.
When incinerated the effect is very different. No problem holding in hand.
I didn’t set it off until I saw someone looking at me.
Late afternoon, solo, radio u/s. Got towed to Lybster and the firm who’d worked on the boat at Wick fixed it for free.
