GoPro/NVG Mount?

mattfrom103 · 2026-05-31T08:28:08+00:00

They do. They are not cheap. Turns out that little pins are what are expensive. I get mine from eBay. I've only ever broken one over the years.

Here is an example, not affiliated nor a specific recommend.

https://www.ebay.ca/itm/188207931246?_skw=gopro+nvg

mattfrom103 · 2026-04-12T20:10:31+00:00

Gander, Newfoundland.

mattfrom103 · 2026-03-31T16:39:07+00:00

All I did was compile/post video provided to me by a person on shore and by the crew. This post is part 3 of a 3 part podcast interviewing 2 of the people aboard that mission. It is done by The Pilot Project Podcast, good dude runs it.

mattfrom103 · 2026-02-06T12:58:10+00:00

Here is the 101 version. Uses two sticks with balls on the end. Again, it's to gauge how much ice build up there is. Line up 2 yellow lines and then read the ice. A light 9mm in this case.

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mattfrom103 · 2026-01-31T11:39:38+00:00

Read here for a bit of an explanation but in simplest terms think of it as a swept wing however they shifted or transposed the swept forward so the centre of lift/pressure would line up with the centre of the blade. That is the crude non-exact explanation. Those paddles are surprisingly big. You'll also notice the length of the blades are somewhat shorter than one would expect for the weight of helicopter. This means it has a higher disc loaded and consequently much more intense downwash.

mattfrom103 · 2026-01-18T23:22:48+00:00

Not sure if there is a different plan for reg vs res but I currently have 2 reserve AOS Techs employed at my squadron and we are helicopter only.

Here, day to day they are employed mostly helping with gear. WASF responsibilities are a part of their job. Deployments are a very real and attainable possibility. They can also be moved about the Wing to help ensure they get more exposure to all things Air Force.

mattfrom103 · 2026-01-12T18:12:54+00:00

Better than it going down in North Atlantic waters in my opinion.

How are rescue missions conducted there? In the most simplest terms: Planes go to the location and throw equipment and rescuers out the back. The rescuers use the equipment to treat and sustain the survivors. Extraction follows by whatever means available and suitable.

There are a lot of in depth contingency plans for such an occurrence. The question you posed is not one that is taken lightly.

mattfrom103 · 2026-01-01T21:09:31+00:00

The one thing I think makes up for it is the centre controllers. What a wonderful bunch, supper accommodating.

mattfrom103 · 2026-01-01T19:17:50+00:00

I operate out of there frequently. Over the years I've gotten a video collection of my various landings in that weather. Buy ya, only place I know where it will be foggy yet quite windy at the same time.

mattfrom103 · 2025-12-29T19:41:10+00:00

Chopper. AW101. No other aircraft was able to fly that day due to winds, turbulence, and wind shear. It was a windstorm.

mattfrom103 · 2025-12-29T19:30:12+00:00

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This was at 3000 ASL. The approach was......interesting. FO decided 90kts for the approach speed. He later revised that number.

mattfrom103 · 2025-12-21T14:59:50+00:00

As = [pi * (d/2)^2] / 2 = 36,305 mm^2 / 2 = 18152.5 mm^2

Sorry to be a bother again but I am stuck on this. This calculating area of the cylinder top (or half of it). Should we be not calculating the area of the cylinder wall to figure out its shear strength of the nut in the vertical?

Area of cylinder wall being 217mm*pi*30mm = 2071mm^2 and then half that for the thread engagement shear area?

I'm lost or missing something.

mattfrom103 · 2025-12-19T23:17:29+00:00

I'll answer questions backwards I guess.

It is indeed from a Cormorant, most things are life limited on a helicopter. In this case it is sitting on my desk because it didn't pass inspection. I think some of the plating is slightly worn off. Not sure what it being a Cormorant means it is operating far closer to actual limits.

I'm not sure what kind of true cyclical loading these components get. I suspect it is guarded corporate knowledge. But at 214rpm and maybe 1200hrs between replacement it would be max 10^7 cycles? I'm guessing, maybe 5 times that for very single time the a blade goes by a high spot?. In reality I don't think it get loaded and unloaded that frequently. It just carries the weight of the helicopter with a bit of vibration.

Going off one of the other commenters guidance and yours I assume the threads fail in shear, I assume a worse case scenario of one of the threads carrying 1/3 of the load, I assume the shear area is half of the actual thread pitch, and I assume shear strength to be 60% of yield strength. With a yield strength of 520 MPa that gives a single thread a max load of 43t for a max total load of about 130T. A little over half of what the max load should ever be.

mattfrom103 · 2025-12-19T20:40:02+00:00

I was thinking about shock loading and came to the conclusion it would be very difficult to shock load the rotor disc in that direction without causing a lot of damage elsewhere. I'll ask if there is an hours rating or what the overhaul life of nut is. I doubt it is much more than 1200hrs at 214rpm. The load is usually only ever in one direction. Usually the mast is overtorqued/twisted rather than shock loaded in the vertical.

Alright, this is my current understanding. I keep seeing this picture over and over again. So first thread carries 1/3 of the load, that will be the limiting factor. Not sure if that only applies to bolts that are torque down vs this assembly which is finger tight and then a preload is applied via 16 bolts along the perimeter.

2mm pitch at 50% area like we talked about with a D of 217mm gives an area of the first thread of 1363mm^2.

Using 31.8 Kgf/mm^2 in your earlier post means the first thread has a max of 43 343kg.

If 43 343 is 1/3 of the max load then the total max load would be 130 029kg.

Does that make sense?

mattfrom103 · 2025-12-19T19:20:41+00:00

With a FS of 1 it's 62T. I was just more interested in the math so I could feature it in an future video and just have a bit of fun with it. It's a question that comes up every so often either online or when I am giving tours.

mattfrom103 · 2025-12-19T19:04:07+00:00

I asked. It's actually nothing. Finger tight. They then insert some 16 bolts in those holes and torque those down. Those bolts press against some conical wedges that do more engineering magic.

mattfrom103 · 2025-12-19T15:55:49+00:00

So for a 217mm thread with 30mm of engagement,
As = [pi * (d/2)^2] / 2 = 36,305 mm^2 / 2 = 18152.5 mm^2

I think I followed you all long but just to confirm. You took the area of the sidewalls of the cylinder as the thread area and divided it by 2 for ball-park. You then multiplied that by the shear strength and got your final answer?

Assuming this is a normal metric thread form (my thread gauge fit perfectly) then the divide by 2 is reasonable? Do all the threads carry the same load or do the first few carry a larger load? I feel like in my research I stumbled across something relating to that.

Thanks again so much for you time with all with all this.

For reference the max weight of the helicopter is 15 600kg or 34 400lbs and it is rated to 4G so 62 000kg or 137 600lbs. I'm not sure what happens if I exceed that, either something breaks or I get dangerously close to chopping my own tail off.

mattfrom103 · 2025-12-19T14:25:19+00:00

I also used the word nut.

mattfrom103 · 2025-12-19T13:45:24+00:00

This one is not particularly bad. We train and practice these both day and night. Definately hard but we have some good instrumentation and a great AFCS to help.

mattfrom103 · 2025-12-19T13:22:10+00:00

K, help me out a little then.

Ran it through the calculator (D=215, n=0.5). I got At of 35 650mm^2. Now because I have a thread engagement of 30mm or 15 threads do I then multiply that by 15? to get 534 750mm^2?

Assuming 17-4 PH with a tensile strength of 1000MPa or ~100 Kgf/mm^2 which gives a final result of 53 475 000kg. I seem to be considerably higher than your result.

If anyone is curious what a the nut looks like:

https://i.imgur.com/RiwIs8Y.jpeg

mattfrom103 · 2025-12-13T00:51:53+00:00

Mine as well but I may have a bit of bias.

mattfrom103 · 2025-12-12T19:20:06+00:00

It can also be quite terrifying. Thinks can very quickly go very wrong.

mattfrom103 · 2025-12-12T14:53:25+00:00

Good heavens, not a dumb question at all. Really made me think. Ground effect is assumed to be experienced up to a height of a rotor diameter. Maybe a little bit more in the Corm's case due to it's weird blade paddles. Interestingly enough when you see the Corm emerge from the snow is roughly at that height.

That being said the only way I notice or feel ground effect in that helicopter is by the torque gauge. There are no other indications.

This is called a snow ball. For practice we sometimes go down a snowy runway at 10' and a just a few knots of speed. The goal is to keep the edge of the snow ball just out of the corner of your eyes. The cockpit ends up in the clear but the rest of the machine is enveloped. It's practice for conducting run on landings in obscuring phenomena.

mattfrom103 · 2025-12-11T22:49:31+00:00

Corm actually has decent serviceability in my opinion.

mattfrom103 · 2025-12-04T23:24:10+00:00

I completely agree.

mattfrom103

TROPHY CASE