Whatzit?

[webenda]

The halteres/counterweights are only found on two blade choppers and two wing insects? A dragonfly/damselfly with four wings doesn't need them and I assume that a 4 or 5 blade helicopter is the same, not needed or no place to put it?

I don't know, lets ask a helicopter pilot.

Bill, why do helicopters like UH-1 have a flybar and ones like the UH-60 don't?

William Blume, Vietnam Veteran helicopter guy.

"I have about 3,000 hr in the UH-1. I have no idea what you mean by a 'flybar'”."

Hmm... We have a helicopter mechanic here on MTJ. Let's ask him.

2railjon, please answer why we don't see stabilizer bars (flybars) on helicopters with more than two blades?

Jon answered, "Hydraulic actuators are now mounted to the top of the rotor hub now that change the pitch."

[chuck]

Thanks Wayne (and John).

I didn't know there is a chopper with 8 blades until I started looking for closeups of the rotor hub. UM Survival Flight was transitioning from their four blade Bell 430's to five blade H155 Eurocopters. Our campus office was just across the Huron River from the chopper landing pads off the side of the hill below the main hospital. We could hear the choppers coming and going. The newer 5 blade machines were supposed to be quieter than the older 4 blade units. I don't think either of them were quiet. You could easily tell the difference when they were on final approach. The four blade units seemed to have a "beat" frequency that was easily discernible. After a while we could tell if the inbound chopper was one of ours and whether it was a 4 blade or 5 blade. The landing pads have a direct tunnel access to the main hospital.

[webenda]

John explained more about helicopter controls.

He let me know. "I was the avionics technician on the Blackhawks not a mechanic."
"The old Huey’s were all cable and pulley controlled where the Blackhawks had rods and link pins incorporated into the AFCS system. The rods and link pin controls were only used as back up if the AFCS system ever failed."

We don't see flybars, stabllizer bars or halteres on modern helicopters because they are fly by wire. The Automatic Flight Control System (AFCS) takes care of everything.

So... question answered for modern helicopters but not for things like the three bladed Sikorsky H-19 Chickasaw.

[chuck]

As a child I had one of these:

https://www.youtube.com/watch?v=t5vX8uivsuI

I remember the sky hook. BTW, my army when were plain green, not the hand painted guys shown in the TV ad.

It was motorized and did taxi around but there is/was no steering wheel. The blades were pretty big and you usually didn't try to run them while holding the chopper off the ground!

[webenda]

More on insect/helicopter flight stability.

If the fly did not have a bio-mechanical mechanism to stabilize its flight, it would need to devote some part of its brain to the task. The fly does not have a lot of brain to spare.

Brain Anatomy (neuron count)
Sponge: 0
Rotifer: 100
Snail: 10,000
Fly: 100,000
Dragonfly: 1,000,000
Honey bee: 1,000,000
Fish: 10,000,000
Hamster: 100,000,000
Parakeet: 1,000,000,000
Bear: 10,000,000,000
Human: 100,000,000,000
Elephant: 257,000,000,000

How important is some sort of stabilization method in a helicopter? I asked Jon.

Wayne: "I wonder if the AFCS failed how rough the landing would be? Did you ever witness such a landing?"

Jon: "LOL, yep! One of the pilots training requirements is to take of and land with the AFCS system shut down. It’s one of the scariest things you’ll ever see! That helo is almost uncontrollable and wobbles everywhere!!"

Disconnecting the fly hateres has a similar affect on the fly.
Reference: https://www.pnas.org/content/112/5/1481

[webenda]

What are these things?

[webenda]

So wrong!

[chuck]

Vintage refractive telescope parts. Eyepieces, parts for an equatorial mount?

[MurphOnMillerAve]

Tools used when servicing and/or repairing motorcycles ?

[Rufus T. Firefly]

Surveyor tool?

[webenda]

Surveyor tool?

At last, I can stop wondering what these are. Indeed, they appear to be eyepieces for a Surveyor's transit. Thank you Rufus.


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Tools used when servicing and/or repairing motorcycles ?

Possible murph. I got them from a mechanic who used them inspecting for cracks and other maladies.
I am not sure why one is mounted in a holder.

Vintage refractive telescope parts. Eyepieces, parts for an equatorial mount?

The telescope part is correct.

What is "so wrong" with the third image is that someone put rubber O-ring in the eyepiece. Both of these eyepieces are of Ramsden design. The focus of the eye element is supposed to be on a graticle or cross hairs placed just beyond the field lens. Adding the O-rings places the focus on the flat surface on the field lens, placing all the dirt on the field lens in sharp focus. When I tried using it way the previous owner was using it, I had to place the object being observed (the point of an HB lead pencil) directly on the field lens.

[Rufus T. Firefly]

Surveyor tool?

At last, I can stop wondering what these are. Indeed, they appear to be eyepieces for a Surveyor's transit. Thank you Rufus.

They just looked "familiar",

[webenda]

Whatzit clue 1

[E7]

Possible murph. I got them from a mechanic who used them inspecting for cracks and other maladies.

They generally do magnafluxing for that.

They were obviously lenses/eye pieces of some sort, but I wasn't sure exactly what! I've seen a few transits, but never used one or even got up close and personal. A late friend of mine was a surveyor.....does that count? LOL


PS: Raspberry Ice Cream! LOL

[MurphOnMillerAve]

Whatzit...
The tip of a finger of a glove (?)