How many rpm do you guys run at cruise?

The Low Wing Wonder
User avatar
domini99
Senior Airman
Posts: 112
Joined: 22 Jun 2014, 13:46

How many rpm do you guys run at cruise?

Post by domini99 »

Hey, i've been told that the cherokee should be faster than the 172...

Am i being too carefull on the throttle? im running 2200/2300rpm on cruise and going about 90/95 knots.
I can't really say this is faster than the 172, because im usually going like 100 knots with it.
I really got the feeling im being too carefull on the throttle, the notebook says i can go up to 2650rpm.....

i mostly cruise at 5000 feet, simply because it looks nice on the altimeter :P

Now how many rpm do you guys run on? and how fast are you going in the cherokee?


And a "Compared to real world" question: When flying 90 knots in both, which one has the lowest fuel consumption? I'm sorry, im a realistic thinker and am constantly thinking like "What if..... in real life?" :roll:

User avatar
Bruce Hamilton
Senior Master Sergeant
Posts: 2251
Joined: 20 Sep 2009, 13:28

Re: How many rpm do you guys run at cruise?

Post by Bruce Hamilton »

I run it at full throttle, as long as it doesn't redline. :mrgreen:

User avatar
pilottj
Senior Master Sergeant
Posts: 1571
Joined: 18 Jul 2008, 16:57
Location: KAPC

Re: How many rpm do you guys run at cruise?

Post by pilottj »

I usually cruise at 2550RPM leaned for peak RPM above 3000', this usually yields around 125MPH IAS.

Cheers
TJ
"The knack of flying is learning how to throw yourself at the ground and miss." - Douglas Adams
Image

User avatar
domini99
Senior Airman
Posts: 112
Joined: 22 Jun 2014, 13:46

Re: How many rpm do you guys run at cruise?

Post by domini99 »

Woah, am i really that easy on the throttle?

Doesn't that burn a lot of fuel?

real
Airman First Class
Posts: 71
Joined: 10 Apr 2014, 10:38

Re: How many rpm do you guys run at cruise?

Post by real »

I normally use the power setting table and cruise at 75% of power. Regards.

Real

pilotgod
Senior Airman
Posts: 232
Joined: 04 Jan 2013, 18:30
Location: Hot Hot Hot, AZ

Re: How many rpm do you guys run at cruise?

Post by pilotgod »

The Cherokee "Hershey Bar" wing is a bit thicker chord than the Cessna wing, therefore its parasitic drag is a little higher. This is where the gap seals, fairing seals, and wheel pants/fairings come in handy. There is a benefit to it though, the Piper's don't tend to float on final like the Cessna; actually, with full flaps and no power, they are a bit closer to an elevator. With that said, both aircraft use the same engine, but different props.

The following are the real world numbers I use for flight planning in a 1968 Cherokee 140/180 with the IO-360 180hp engine. At 6000, I have cruise as 2400 RPM for a burn rate of 7 gph at cruise. Now this airplane has the wing root fairings, but no wheel pants or gap seals. I get a true airspeed of 103 kts on average. If I have it loaded, this will drop down to about 97, but usually this plane I fly alone. When I take friends/family, I opt for the Arrow with its 200hp engine and retractable wheels. Don't forget that KIAS is NOT KTAS. KIAS (Knots Indicated AirSpeed) is what the Airspeed Indicator is showing you in the cockpit. KTAS (Knots True Airspeed) is your actual speed through the air. KTAS is basically, your Indicated Airspeed corrected for air density (this is why the Cessna ASI has the correction window where you dial in the temp difference) and basically, your True Airspeed is greater than Indicated Airspeed as you climb to thinner air. At 6000 ft, the difference is approx 5-6 knots. So the ASI may show 97, but the True Airspeed is 103.

With all that said, I don't have to pay for fuel in the A2A Cherokee, so I fly it at 2400 for cross country and 2500 for closer hops. Then again, I have all the speed mods on unless I am going to a grass strip and for the sake of authenticity, I will take the wheel pants/fairing off, but the gap seals and root seals stay on.
System Specs:
Intel i7-2600 @ 4.3GHz, ASUS P8P67-Deluxe, 8GB DDR3-1600, ATI Radeon HD7770 (2GB), OCZ Vertex 250GB SSD (OS), Seagate 1TB HDD (Data)
FSX w/Acceleration and tons of add-ons.

User avatar
domini99
Senior Airman
Posts: 112
Joined: 22 Jun 2014, 13:46

Re: How many rpm do you guys run at cruise?

Post by domini99 »

pilotgod wrote:The Cherokee "Hershey Bar" wing is a bit thicker chord than the Cessna wing, therefore its parasitic drag is a little higher. This is where the gap seals, fairing seals, and wheel pants/fairings come in handy. There is a benefit to it though, the Piper's don't tend to float on final like the Cessna; actually, with full flaps and no power, they are a bit closer to an elevator. With that said, both aircraft use the same engine, but different props.

The following are the real world numbers I use for flight planning in a 1968 Cherokee 140/180 with the IO-360 180hp engine. At 6000, I have cruise as 2400 RPM for a burn rate of 7 gph at cruise. Now this airplane has the wing root fairings, but no wheel pants or gap seals. I get a true airspeed of 103 kts on average. If I have it loaded, this will drop down to about 97, but usually this plane I fly alone. When I take friends/family, I opt for the Arrow with its 200hp engine and retractable wheels. Don't forget that KIAS is NOT KTAS. KIAS (Knots Indicated AirSpeed) is what the Airspeed Indicator is showing you in the cockpit. KTAS (Knots True Airspeed) is your actual speed through the air. KTAS is basically, your Indicated Airspeed corrected for air density (this is why the Cessna ASI has the correction window where you dial in the temp difference) and basically, your True Airspeed is greater than Indicated Airspeed as you climb to thinner air. At 6000 ft, the difference is approx 5-6 knots. So the ASI may show 97, but the True Airspeed is 103.

With all that said, I don't have to pay for fuel in the A2A Cherokee, so I fly it at 2400 for cross country and 2500 for closer hops. Then again, I have all the speed mods on unless I am going to a grass strip and for the sake of authenticity, I will take the wheel pants/fairing off, but the gap seals and root seals stay on.
i know about the difference between indicated and true airspeed, i was just curious how fast everybody was going in indicated airspeed on which power settings. I'm always trying to burn as less as possible fuel, but i was thinking i was going a bit ridiculously underpowered.

I haven't found the fuel flow indicator on the cherokee yet, i don't think it has one. (Or i'm blind, also a possibility :p )

User avatar
lonewulf47
A2A Chief Pilot
Posts: 6744
Joined: 03 Aug 2008, 10:41
Location: 1 NM east of LSZH

Re: How many rpm do you guys run at cruise?

Post by lonewulf47 »

Sorry If I may step in here with a completely different approach to the initial question: Why for God's sake does nobody ever have a look at the manual? It's all there between pages 71 and 74. It does not need any special advice or personal tips and tricks. Just take the figures from the manual and you know exactly what you get ! Is that really soooo complicated... 8) 8) 8) :wink: ???
Oskar

ASUS MAXIMUS XI Hero, i9-9900K 8 Core OC 5.2 GHz, WIN10-64Bit, 32GB DDR5, Nvidia RTX 2080 Ti Strix, 2x 2 TB SSD M.2, 1x 2 TB SSD, 1 monitor 4k, AS4, EFB on remote PC

Image

User avatar
domini99
Senior Airman
Posts: 112
Joined: 22 Jun 2014, 13:46

Re: How many rpm do you guys run at cruise?

Post by domini99 »

lonewulf47 wrote:Sorry If I may step in here with a completely different approach to the initial question: Why for God's sake does nobody ever have a look at the manual? It's all there between pages 71 and 74. It does not need any special advice or personal tips and tricks. Just take the figures from the manual and you know exactly what you get ! Is that really soooo complicated... 8) 8) 8) :wink: ???
I'm often just curious what others do. On our flying club one flies his 172 at 60/70 knots with barely any throttle while another races the thing with 120 knots through the air. I've seen some people landing with and without flaps... Not everybody flies the same :). I'm just really nervous on my fuel indicators and tend to fly more slowly, I was curious how others fly the thing, and apparently I'm the airsnail going only 90/100 knots :lol:

I'm still learning the Cherokee, I'm now having only 3 flight hours in it.

User avatar
taildraggin68
Senior Master Sergeant
Posts: 2411
Joined: 14 May 2014, 18:26
Location: Florida

Re: How many rpm do you guys run at cruise?

Post by taildraggin68 »

lonewulf47 wrote:Sorry If I may step in here with a completely different approach to the initial question: Why for God's sake does nobody ever have a look at the manual? It's all there between pages 71 and 74. It does not need any special advice or personal tips and tricks. Just take the figures from the manual and you know exactly what you get ! Is that really soooo complicated... 8) 8) 8) :wink: ???

Lol, it might just be, we all know how "manuals" are such fun reading :D (USAF PME manual for example) I usually run at around 2300 to 2400 rpm between 3000 to 5000 alt and can usually maintain 7gph depending on mixture, of course I'm not there to fly fast, just fly and look out the windows on my way to where ever I decide to venture. :D

User avatar
domini99
Senior Airman
Posts: 112
Joined: 22 Jun 2014, 13:46

Re: How many rpm do you guys run at cruise?

Post by domini99 »

taildraggin68 wrote:
lonewulf47 wrote:Sorry If I may step in here with a completely different approach to the initial question: Why for God's sake does nobody ever have a look at the manual? It's all there between pages 71 and 74. It does not need any special advice or personal tips and tricks. Just take the figures from the manual and you know exactly what you get ! Is that really soooo complicated... 8) 8) 8) :wink: ???

Lol, it might just be, we all know how "manuals" are such fun reading :D (USAF PME manual for example) I usually run at around 2300 to 2400 rpm between 3000 to 5000 alt and can usually maintain 7gph depending on mixture, of course I'm not there to fly fast, just fly and look out the windows on my way to where ever I decide to venture. :D
Exactly :)

EnDSchultz
Technical Sergeant
Posts: 504
Joined: 24 Feb 2014, 20:05

Re: How many rpm do you guys run at cruise?

Post by EnDSchultz »

Bruce Hamilton wrote:I run it at full throttle, as long as it doesn't redline. :mrgreen:
Me too. I only ever really let off the throttle during descent and landing. More wear on the engine...more likely for an interesting failure to happen! :lol:

Rudyjo
Senior Airman
Posts: 205
Joined: 10 Mar 2012, 15:47

Re: How many rpm do you guys run at cruise?

Post by Rudyjo »

domini99 wrote:Woah, am i really that easy on the throttle?

Doesn't that burn a lot of fuel?
As long as your putting it on the A2A credit card, don't worry about it.

n454mw
Staff Sergeant
Posts: 354
Joined: 01 Apr 2010, 23:17
Location: West Texas

Re: How many rpm do you guys run at cruise?

Post by n454mw »

In cruise I run 2500 on both the Cherokee and the 172 but just because that is what I was taught in flight school. It probably isn't the best but old habits die hard.
Thanks Mark

robert41
Senior Master Sergeant
Posts: 1538
Joined: 02 Jan 2006, 20:42
Location: WI USA

Re: How many rpm do you guys run at cruise?

Post by robert41 »

I usually cruise at 2500RPMs. At lower altitudes, 3-5000ft this gives me near 140IAS. Leaned for about 8-9GPH. Not bad if you look at the P51, it idles at 9GPH. The shift2 panel shows about 10kts faster (ground speed) than the 172. The 172 I cruise at 24-2500RPMs.

new reply

Return to “Piper Cherokee 180”

Who is online

Users browsing this forum: No registered users and 5 guests