Cyclic and Collective sticks, what does the buttons do?

[moldy oldy]

The flight manual includes detailed pics of the cyclic and collective, including the functions of each button/switch. Hopefully the flight manual will be released to the public soon!

 

I can say this for sure, though: Helicopters don't have "force trim hats". ;)

Sorry Alpha one six I must disagree, I have flown quite abit in legacy aircraft such as Hiller, Enstrom, Kaman, Hughes, and Schweizer and all of the models I have experience in have a trim hat on the cyclic that functioned electrically through motored spring displacement for cyclic load for trim. If one looks at current military aircraft in the U.S. Army, the mh-6 and the uh-60 do have a funtioning trim hat just like their civilian counterpart. On the uh-60 you have the option of trim hat and gradient disconnect with a button. This is an interesting thread thanks for making me pull out my manuals.

[mvsgas]

What is the difference between "force trim hat switch" compare to a "trim hat switch"? What is force trim?

[moldy oldy]

What is the difference between "force trim hat switch" compare to a "trim hat switch"? What is force trim?

mvsgas yours is a much more difficult question to answer than one might expect at first blush. There are two different types of flight control systems in helicopters. One is the mechanical system and the other is the boosted system. In both types of systems you have a means of applying friction to the controls, this keeps rotors from doing unpected actions during startup and shutdown. It also enables the indivdual pilot to apply a level of friction that is comfortable for him/her.

 

In flight, force trim allows the pilot to trim off pressure in the controls and also will allow the pilot to release the controls for short duration actions such as tuning a radio or picking up a map. If the aircraft is hit by a wind gust or becomes dynamicly unstable the force trim will allow it try to return to its approximate pre upset attitude.

 

Force trim hat switch would generally relate to spring or a brake gradient form of cyclic positioning. However in some systems the aircraft will have a stability augmentation system which trys to hold attitude by gyros in which case the attitude would be adjusted by using a trim hat switch. The result is the same but the means is different.

 

In the unboosted system a certain amount of feedback will come back through the linkage from the rotating dynamics and some of this is mitigated by the springs in the linkage. The controls can still be moved against the force trim but will want to return to the prepostion.

 

In a boosted system without the force trim engaged or friction applied the controls can move without a pilot induced action if the controls are released.

[Cowboy10uk]

 

There is a "throttle" in name, but it does not require adjustment during flight. On the Ka-50, there is no twist throttle, Ka-50 also has an incr-decr switch for rotor RPM, sort of. It's on the collective.)

 

Perfect Thats just what I wanted To know Alpha, It means I Don't have to find a way to mount one of my collective :D Less work means It will be here quicker.

 

 

Just hope it works well enough for BS.

 

 

Cowboy10uk

Edited September 4, 2008 by Cowboy10uk

[Zorrin]

I think that's a flawed argument.

 

On older helicopters, and some current ones (Robinson R-22, for example), you have to manually control the throttle in order to keep the rotor speed within the proper operating range. All (almost all?) modern turbine powered helicopters do this automatically. There is a "throttle" in name, but it does not require adjustment during flight. On the Ka-50, there is no twist throttle, there are throttle levers...one for each engine. When you start the engines, they are in the lower-most detent, called "IDLE". After the engines are started and warmed up, you move these levers up to "AUTO", and you're done. You never touch them again unless you lose an engine or you land and you're ready to shut them down. The Mi-17 and Mi-24 have a twist throttle, but again, in normal operation, it's all the way left for "IDLE" and all the way right for "AUTO", and it's never touched in-flight unless there is a problem. If the rotor RPM needs to be adusted, there is a seperate incr-decr swtch for that. (The Ka-50 also has an incr-decr switch for rotor RPM, sort of. It's on the collective.)

 

The fuel controls on modern engines automatically adjust fuel flow rates to keep the rotor RPM within a certain range (or at a specific percent), so the pilot does not touch the throttle during flight except in case of some kind of emergency. And "I need more power" is not that kind of emergency, I'm talking about the failure of an engine or the overspeed of an engine.

 

In other words, the helicopter is way smarter than the pilot at determining how much fuel to put into the engines in order to keep the rotor RPM where it needs to be. To try to compare it to a car throttle, you'd have to assume that the car is permanently set on cruise control for a specific speed. Once you set the cruise control, you never touch the throttle again until you turn off the cruise control. During "cruise", your car's computer determines how much fuel to send into the engine in order to maintain your set speed. Now imagine that this "cruise control" is always on, from the moment you turn on your car, until you turn it off, and all you can set your throttle to is "IDLE" and (for example) "50km/hr", then that would be like a helicopter's throttle.

 

Of course. You misinterpreted my post, which I will agree could've been better worded. But the fundamental fact is you cannot start a turbine engine with the FADEC engaged. Simply not possible.

 

Acutally an R22 comes standard from the factory with a governor. However, during the start-up procedure you are required to "split the needles" (by chopping the throttle you reduce the engine RPM and are making sure that the rotor rpm doesn't drop with the engine RPM) on and only after you have checked the clutch mechanism rotates freely without the engine then you can wind up the throttle and engage the governor. I can't remember the exact figure for RPM before switching the governor on as I haven't flown a 22 for quite some time, after that the governor is indeed switched on and it can be forgotten about.

However, in a governor failure situation you would have to manually adjust the throttle with the collective.

 

Take the Bell 206, as an example of turbine heli.

Has a twist throttle on the collective. You are required during start-up of the non-FADEC equipped versions to adjust the throttle to keep the temperature below something like a max of c900ish degrees C.

 

Once started you can engage the governonr.

 

And I beg to differ about it being a "flawed argument". You wouldn't get into a car and drive it if you knew there was no way you could control the throttle. Whether it was autonomous or not. By its very nature anything mechanical will break.

 

Anything man-made will break.

 

So by that token, I obviously no sweet f**k all about the KA50 and its systems.

 

What kind of redudancies are there on the KA50?

[mvsgas]

mvsgas yours is a much more difficult question to answer than one might expect at first blush. There are two different types of flight control systems in helicopters. One is the mechanical system and the other is the boosted system. In both types of systems you have a means of applying friction to the controls, this keeps rotors from doing unpected actions during startup and shutdown. It also enables the indivdual pilot to apply a level of friction that is comfortable for him/her.

 

In flight, force trim allows the pilot to trim off pressure in the controls and also will allow the pilot to release the controls for short duration actions such as tuning a radio or picking up a map. If the aircraft is hit by a wind gust or becomes dynamicly unstable the force trim will allow it try to return to its approximate pre upset attitude.

 

Force trim hat switch would generally relate to spring or a brake gradient form of cyclic positioning. However in some systems the aircraft will have a stability augmentation system which trys to hold attitude by gyros in which case the attitude would be adjusted by using a trim hat switch. The result is the same but the means is different.

 

In the unboosted system a certain amount of feedback will come back through the linkage from the rotating dynamics and some of this is mitigated by the springs in the linkage. The controls can still be moved against the force trim but will want to return to the prepostion.

 

In a boosted system without the force trim engaged or friction applied the controls can move without a pilot induced action if the controls are released.

Thank you for the info. I'm sure glad I'm not a mechanic on those things, fly-bi-wire is so much easier to work with from what I gather.

[AlphaOneSix]

Sorry Alpha one six I must disagree, I have flown quite abit in legacy aircraft such as Hiller, Enstrom, Kaman, Hughes, and Schweizer and all of the models I have experience in have a trim hat on the cyclic that functioned electrically through motored spring displacement for cyclic load for trim. If one looks at current military aircraft in the U.S. Army, the mh-6 and the uh-60 do have a funtioning trim hat just like their civilian counterpart. On the uh-60 you have the option of trim hat and gradient disconnect with a button. This is an interesting thread thanks for making me pull out my manuals.

 

I'm not talking about trim in the context of autopilots (or stability augmentation systems, or its many other names). I'm just talking specifically about force trim. There isn't a hat for it because it's not something that you can go four or more directions with. It's on, or it's off. On every aircraft I've seen, it's a switch and/or a button.

 

I agree that some aircraft have trim hats that work with AP/SAS/SCAS/etc., but that is something completely different than force trim.

 

Anyway, I think we're on the same page, we're just getting into the semantics of a hat switch versus a regular switch or button.

[AlphaOneSix]

Zorrin, thanks for the clarification, I have practically zero experience with the R-22, but have a friend who flies them. Your post was very informative for me and I see where you're coming from.

 

With regard to the Ka-50, what kind of redundancies are you looking for? Engine controls?

[Zorrin]

Well if whatever governor or whatever else is metering the engine rpm fails, how do you control the engine rpm?

 

Obviously with no experience of twin-turbine helis I can't compare it to anything else. I just find it odd that there isn't a throttle. I can understand that the condition levers which would be moved from cut-off to idle to full/auto or whatever. Yes that makes sense but what happens happens if your governor fails on the KA50?

 

In my mind when you posted about the "levers that you move from idle to auto", to me in my head they seem to be condition levers. But I'm happy to accept they're the "throttles" until I get my hands on a KA50!

 

Again I don't know anything of the systems in the Shark so I can't really ask you more specifically other than what else is there in the engine/rotor management?

Edited September 4, 2008 by Zorrin

[Yellonet]

Seems like this thread went off-topic pretty fast :(

[ThunderChief]

the fundamental fact is you cannot start a turbine engine with the FADEC engaged. Simply not possible.

 

Uhhm the only jetengine I ever started had the FADEC engaded all the time (it was a JetCat only, but still a real jet engine). I think what makes the FADEC special is that it can control the engine in situation: Full Authority ;)

But of course I could be wrong ...

 

And I agree that its very unlikely that you can start a non-FADEC engine with the govenor engaded, because those mostly analogous systems have a very limited operating bandwidth.

Edited September 4, 2008 by ThunderChief

[Zorrin]

Uhhm the only jetengine I ever started had the FADEC engaded all the time (it was a JetCat only, but still a real jet engine). I think what makes the FADEC special is that it can control the engine in situation: Full Authority ;)

But of course I could be wrong ...

 

And I agree that its very unlikely that you can start a non-FADEC engine with the govenor engaded, because those mostly analogous systems have a very limited operating bandwidth.

 

The only jet engine I've touched with a FADEC was Cessna's Citation Mustang.

It was a simple start procedure, just click the throttle through the idle cut off detent and then press the starter. But the FADEC didn't take control until the engine had reached something like 44% or 48% N1 (I can't remember the exact figure now but you saw the colour change on the avionics display to notify you that the FADEC was now "in charge").

 

So we're both right and wrong!

 

And Yellonet - not really off-topic as it's still related to the Ka50 and it's controls... Sort of... :music_whistling:

[AlphaOneSix]

Yes, the throttles on the Ka-50 would be better labeled as "condition levers", at least in my opinion. The Mi-17, for example, has condition levers, but they are never touched during normal operation, you use the twist throttle to go from full left (ground idle) to full right (flight, or what the Russians call "auto"). On the Ka-50, this is accomplished using the condition levers, similar to the AH-64 (which I am more intimately familiar with). The equipment on the Ka-50 labeled "engine governor" is more related to shutting off the engine in the event of overspeed, and restricting the fuel flow in the event of an overtemp. The fuel controls on the TV3-117 are completely mechanical and extremely reliable.

 

The condition levers on the Ka-50 have four detents: IDLE, MEDIUM, AUTO, and FULL. As far as I can tell in-game, you can only be in one of those 4 positions, but I suspect the actual aircraft can have them placed anywhere along their travel. I don't know how accurate this is, however, since I spend most of my time proofreading the manual and less time actually flying. I'm not completely sure how to use the "MEDIUM" detent, but I do know that you pull an engine's throttle up to "FULL" if the other engine fails

[-sulan-]

Very interesting thread me thinks!! :thumbup:

 

Question: Since the Governor keeps the rotor in it's proper rpm, why do you need to fiddle with the incr/decr governor switch in flight?

Btw, is the governor switch nr 5 on the collective in the OP's picture?

[nemises]

I Guess the govener operates on a standard set of conditions (Fuel flow / air pressure etc..) to determin the goal RPM?

however, as (I think) Alpha said above, if one of the engine cuts out, the Govenor will not be aware of that, and would still be trying to keep the single remaining engine running at peak RPM, however, peak RPM on a single engine would not be enough to drive the rotor effectively in flight. RPM must be increased on the single remaining engine to so provide more power to the whole drive train to compensate. To tell the govenor to do this, you would use the govener increase rpm switch presumably.

 

I'm guessing as well, that this function is used in standard flight to compensate for altitude / fuel mix ?

 

All guesses, but I do find this fascinating.

[Triggerhappy69]

Hey Guys, Just a quick Question, Im currently trying to build my own collective as there are none with a good price avalible, Can someone answer a very stupid Question. :) The Hokam collective, Does have a throttle on the collective right, Or is the throttle control Now controlled by computers, and all you have to do is raise and lower the collective, rather than having to roll on and off, as you move the collective. I know when the answer comes back I will kick myself, But I just want to be 100% sure Before I try and add the throttle.

 

Cheers

 

Cowboy10uk

 

 

I would check out URZE's Collective on http://www.leftside-limited.com/collective.html If I were you..! At least you can be sure it works perfectly, and has all the functions you might need for the KA-50..

 

Or you can build one yourself like I have? I have attached the E-Drawings file in RAR format for you to download..!

 

 

This is the end result:

 

 

Here's the RAR file for you:

 

[ATTACH]19189[/ATTACH]

 

 

 

Just open it and it will self-install.. :thumbup:

 

Ps. If you want to see HOW to make this, just check out my thread on : http://forums.eagle.ru/showthread.php?t=27270&page=34

Edited September 5, 2008 by Triggerhappy69

[hannibal]

wow..

your creation is looking good...

 

unfortunately, my sim pit is being dismantled and being put into storage...

i revisit the world of helicopter sims when ever DCS Black Shark comes out...

 

 

photo of my collective and cyclic in the closet....

[Cowboy10uk]

Hi Triggerhappy, WOW man, That is more than genious sharing your plans like that, Not too sure how I can thankyou. I've looked at Leftsides collective, and Would be intrested to see it working, Though i'm impatient so trying to do one myself :D However after seeing your plans, i think I will throw mine in the bin and start again. Thanks again.

 

Cowboy10uk

[urze]

Hi Triggerhappy, WOW man, That is more than genious sharing your plans like that, Not too sure how I can thankyou. I've looked at Leftsides collective, and Would be intrested to see it working, Though i'm impatient so trying to do one myself :D However after seeing your plans, i think I will throw mine in the bin and start again. Thanks again.

 

Cowboy10uk

You are right about his plans - I would really like to help Triggerhappy in building up a website or even give him a section in my webspace - so that his outstanding effort will not go under when he is done. Similar to this: http://www.su27.de/

By the way: Now you can see a video of a prototype in action on my site http://www.leftside-limited.com/collective.html

 

To Hannibal:

I really like your work, but could you please lower the resolution of your posted image so that following/answering this thread will be not so difficult- even on a 22" monitor?

I think a click able Thumbnail would do the job.

Edited September 7, 2008 by urze