Now that I've got a CH Flightyoke with the three levers for throttle, prop, and mixture... I'd like to learn about using the complex stuff. I really don't know much at all about flying the 182 or any other plane with the prop pitch lever. Can someone point me to a tutorial on this?

Rick Lee
www.rickleephoto.com
AIM: RickLeeFS

• RE: Complex prop, throttle,jerryrosie, 13:49z, 12-06-01
  • RE: Complex prop, throttle,Mike_Greenwood, 16:19z, 12-06-01
    • RE: Complex prop, throttle,jerryrosie, 13:58z, 12-07-01
      • RE: Complex prop, throttle,Mike_Greenwood, 16:13z, 12-07-01
• RE: Complex prop, throttle,Mike_Greenwood, 17:13z, 12-07-01
  • RE: Complex prop, throttle,Ben Chiu, 03:05z, 12-08-01
• RE: Complex prop, throttle,RandyHaskins, 02:27z, 12-08-01
  • RE: Complex prop, throttle,RickLee, 14:49z, 12-09-01
    • RE: Complex prop, throttle,jerryrosie, 15:04z, 12-09-01
    • RE: Complex prop, throttle,jerryrosie, 15:12z, 12-09-01

>>Can someone point me to a tutorial on this? <<

Gunner wrote up a good one in the old FSFORUM, as I remember. If Greenie doesn't jump in here, ask him if he has it somewhere in the archives....

***Reality - the refuge of those who can't handle simulation***
Cheers, Jerry (N94)

>>Gunner wrote up a good one in the old FSFORUM, as I remember. If Greenie doesn't jump in here, ask him if he has it somewhere in the archives....<<

Was it a file or a forum message? Files I have, messages are spotty. I never really kept all of the messages, but I do have quite a few. They're a real pain to search through though.

--Greenie
**6 miles SSE KSJC**

Thought it was a file - goes all the way back to FSFORUM and FS5.x......Wouldn't even guess at what the title might be....

***Reality - the refuge of those who can't handle simulation***
Cheers, Jerry (N94)

>>Thought it was a file - goes all the way back to FSFORUM and FS5.x......Wouldn't even guess at what the title might be....<<

OK, if it's a file, I can search for it. I'll see what I come up with.

--Greenie
**6 miles SSE KSJC**

Hi Rick,

I can't find that file Jerry mentioned, so either it was purged previously, or was a forum message. So, let me take a stab at it, then the real pilots can come in and rip me to shreds <g>.

In a typical fixed pitch prop, the engine RPMs and power output are detirmined by the throttle setting. In a variable pitch prop, throttle is used to control the engine power output, but engine RPMs are determined by the pitch of the blades controlled by the prop lever (and/or governor).

This is analogous to the gears in a car. When you first start out, you want a low gear, and high engine power. As your speed increases, you shift to a higher gear, and lower engine power. As you know to go 30mph in 1st gear requires high engine RPMs as opposed to 3rd gear, which results in the same speed but much lower RPMs. This increases fuel economy, and therefore range, and results in much less wear and tear on the engine.

Same on the airplane, but instead of gears, you adjust the pitch of the blades to take a bigger "bite" of air (higher gear) which subsequently requires less RPMs (and power) for a given airspeed. So for takeoff, you would want full engine power (throttle), and high RPMs (prop), as you transition to cruise, you would reduce engine power, and increase the prop pitch to maintain your desired airspeed at a lower RPM setting.

Clear as mud now? I hope it helps a little anyway

--Greenie
**6 miles SSE KSJC**

>Clear as mud now? I hope it helps a little anyway

That pretty much sums it up. Great job, Mike!

The only tutorials that *I* know of are the ones in my books. The only thing I might add to Mike's write up is prop adjustments to high pitch/low RPM is only done at cruise and sometimes kept during descent, and there's a slight adjustment done 500' AGL on climb out after takeoff to keep things under redline. Everything else is pretty much done at low pitch/high RPM.

The power and prop settings used for cruise vary for the desired fuel burn and airspeed at cruise altitude. I published a bunch of cruise charts for the 182S in my FS98 book (I published cruise charts for the Mooney, 182RG, and KingAir in my FS2K book), but this may help for the 182S:

I currently fly a 2000 182S with an IFR student about 4 hours a week and we use 22" and 2,300 RPM for cruise at mid alts (4-8k).

Hope this helps!
Ben

Hi Rick,

>>Now that I've got a CH Flightyoke with the three levers for throttle, prop, and mixture... I'd like to learn about using the complex stuff. I really don't know much at all about flying the 182 or any other plane with the prop pitch lever. Can someone point me to a tutorial on this?<<

If you happen to have the Pilot's Handbook from FS2K or look for ac_books.pdf in the Help folder in FS2K2 you can read on the sections for the Cessna 182. In those you will find what settings to set the prop and throttle during flight.

-Randy

Thanks to all who replied. I have found that the info in the FS manuals and most of the other things I've read just oversimplify the explanations. It's like people think it's so simple that it ought to be really easy to understand. ("You just do this and then do this... simple") But if you don't have a basic understanding of the concepts, the explanations don't make a lot of sense. I've been in touch with Gunner and Barry Wallis via email. Barry sent me this link: http://www.avweb.com/articles/pelperch/pelp0016.html which is a really good article by John Deakin. Man... it REALLY starts at the beginning. It starts off with the early days of aviation when all props were fixed and explains the problems with fixed props and why variable pitch props were invented in the first place. I haven't finished the article yet, but I think I'm finally on my way to getting my brain wrapped around the concept. I recommend the article to all.

Rick Lee www.rickleephoto.com

Hi Rick/Greenie

I found what I thought was a file from Gunner but was really a post from Terry Carroway. I had filed it away back in the old days and quote it here for what it may be worth

#: 1028856 S2/MS Flight Simulator (CIS:FSFORUM)
09-May-97 08:31:27
Sb: CS Prop And Mixture
Fm: Terry Carraway 70441,2071
To: Stuart Jewell 73670,1673
Replies: 0 TID: 230411 Par: 1028813 Chd: 0 Sib: 0

Stuart,

Real life useage of Mixture and CS prop.

Mixture - Anytime in cruise or in a climb over 5,000 feet MSL (rule of thumb) you should lean themixture. What this does is to reduce the amount of fuel delivered to the engine to balance with the reduced air density at altitude. If the aircraft does not have an EGT (Exhaust Gas Temperature) guage, you lean (pull Mixture control back) until the engine runs rough, then enrich (pus forward) a little bit until the engine just runs smoothly. With an EGT you lean until the EGT peaks, then depending on the cruise power setting you adjust the mixture in relationship to the peak. For cruise at 65% or less you can lean up to 100 degrees lean side of peak (after you hit the peak, lean until the EGT falls 100 degrees). For higher power settings (climb or high cruise) you normally richen the mxiture to 50 - 100 degree EGT drop from peak. Of course if the engine runs rough, you richen to smooth operation.

Constant Speed Prop - For takeoff you use max RPM setting. Normally for climb you reduce to 2500 RPM and 25 inches of manifold pressure (nothing magical, just a rule of thumb). There is lots of support for full power climbs though. Once leveled off in cruise you set the RPM to get the desired cruise pwoer setting from the manual. For best performance (power versus fuel useage) the best setting is the lowest RPM with the highest manifold pressure to get the % power desired. WIth you make power changes you need to make sure that you increase RPM before increasing manifold pressure, and reduce manifold pressure before reducing RPM.

You may hear of over square and under square operation. This is a OLD wives tale about the relationship between RPM and manifold pressure. Those who stil stick by this feel you will damage an engein by running it with the manfold pressure in inches higher than the RPM in hundreds of RPM (like say with 26 inches and 2500 RPM). This is BS. On every takeoff you run over square and most turbo charged engiens run oversquare ALL the time. And if thos enumbers are so magic, how do they do it in metric countires where they don't use inches of manifold pressure?

Terry

***Reality - the refuge of those who can't handle simulation***
Cheers, Jerry (N94)

>>Barry sent me this link: http://www.avweb.com/articles/pelperch/pelp0016.html <<

BTW Thanks for that link! Good reading. John Deaken is a regular over in AVSIG as you probably know.....

***Reality - the refuge of those who can't handle simulation***
Cheers, Jerry (N94)