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Creep Feed Grinder
14th Jun 2007, 13:35
Looking for real world experience in the cost of ownership, particularly GPH of a Piper Archer 181.

Thanks
CFG

wsmempson
14th Jun 2007, 14:01
I've just bought an Archer II with a 140 hr factory overhauled engine, so it's probably running as well as one can expect.

If you don't lean it in the cruise, expect 38-40 lph. If you lean it and cruise at 3,500ft on 2350 rpm, you can expect 32 lph.

If I flew higher, I might do better, but this is the SE of England we're talking about....!

gcolyer
14th Jun 2007, 14:01
I fly an archer along with a few other aircraft and realistically it burns 40 ltr an hour which is 8.7987663 Imperial gallons or 10.566882 U.S gallons.

IO540
14th Jun 2007, 20:53
That's a lot - my TB20 does a verified 138kt IAS at 2000ft on 10.5GPH (39.7 litres/hr). And a lot more at FL100, also at 10.5GPH.

gcolyer
15th Jun 2007, 08:09
IO

Is that Imperial or US gallons?

S-Works
15th Jun 2007, 08:11
I agree with IO540 that is a lot. My 210hp Cessna does 36lph low level and 30-32 in the airways.

gcolyer
15th Jun 2007, 08:18
Oh well...win some loose some.

The PA32 300 I fly burns about 70ltr an hour. The Cessna 337 burns about 70 ltr an hour.

So i guess the cost offset come in to over all running cost. It costs more to maintain the 337 than it does the PA32. And I would guess it costs more to maintain a TB20 or C210 than it does a PA28 (Archer).

So all in all swings and round abouts.

S-Works
15th Jun 2007, 08:20
Are you sure on those figures. My Seneca has 2 engines and does that an hour. The Lance that I teach on does around 50-55lph.

70 seems a lot. Are you leaning it!

gcolyer
15th Jun 2007, 08:25
Sure as sure can be with the figures. They are both heavy aircraft and they are both old. Yep I lean them off and on average run at 65-70% power. I usually fly them on maximum weight as well, I don't see the point in flying 6 or 7 seaters with 2 or 3 people in them.

Oh and I am glad your sceneca has 2 engines:eek:

I went up crop dusting with my mate in states in a Sceneca....that was fun.

gasax
15th Jun 2007, 08:27
In round terms you can determine the fuel consumption by multiplying the specific fuel consumption by the power you use. 0.4lbs to 0.45 per hour is about the average consumption for a lycon, with all the gadgets (GAMI, LASAR etc) added you might get 0.38 or so.
Sometimes an interesting thing to do as 'good consumption' is often at lower than book crusie speeds and great speed usually brings along very high consumption. Anything much over 75% usually means a lot of 'fuel cooling' is going on.
On antiques like the Gypsy the 'sweet spot' is the highest throttle opening before the 'power valve' in the carburetter opens, with a Lycon it is usually CHT or EHT driven.

Creep Feed Grinder
15th Jun 2007, 08:47
Thanks for that chaps.

Is there anything that can be fitted to the existing engine to improve the economy?

S-Works
15th Jun 2007, 09:15
Is there anything that can be fitted to the existing engine to improve the economy?

A wheel clamp....

gcolyer
15th Jun 2007, 09:23
or a Cambria cover and control lock.

Creep Feed Grinder
15th Jun 2007, 09:40
Ok, throw someone a line!:D
Aside from the obvious immobilisers, I was thinking more performance enhancing fitments.
NOT suggesting I want to ‘’Pimp up mi wheels’’.

S-Works
15th Jun 2007, 09:54
K&N filter and a gap seal kit will improve the performance and thus allow you to throttle back a bit to save fuel otherwise you are where you are.

owenlars
15th Jun 2007, 13:08
Our PA32 300 plan on (including taxi etc)13 Imp galls per hour or about 60 litres per hour at IAS 130kt. Never let me down yet and always tallies with wing gauges which of course are in US Gall!!!!

gasax
15th Jun 2007, 13:28
Souping up an O-360?

Not fuel injected but the mod is too expensive to consider in the UK.

K&N filter, LASAR ignition may be possible off the back of current approvals and STCs - worth a couple of percent. The powerflow exhaust isn't yet approved for the 181 just 180 under s/n 1761, but it would be the simple best improvement judging by its effect on the other aircraft the system is fitted to.

Knots2U are probably the best bet.

gcolyer
15th Jun 2007, 14:17
owenlars

What PA32 is it? Mine is a 1967 PA32 Cherokee 6 which is the old 7 seat variety with the plunger style throttle, prop and mixture control and not the quadrant type.

If I run at 65-70% i cruise at 120kt at the burn of about 70ltd an hour.

Kiltie
18th Jun 2007, 22:08
Are gap seal kits CAA approved for EASA C of A aircraft or are there expensive modification fees?

tacpot
19th Jun 2007, 03:22
Microlon treatment saves fuel by reducing internal friction. This also results in lower CHTs. The treatment also stops the piston rings locking in place, resulting in better sealing and higher compressions, thereby recovering more of the energy in the fuel, and reducing oil consumption. Microlon don't make a specific claim as to how much fuel you will, but it's usually at least 5% and sometimes nearer 10%. Even at 5%, this saving will pay more for the treatment on a 2000 hr TBO engine. Less fuel burnt is also better for the environment.

K&N Airfilters can save another 5%.

Airspeed Aviation can advise on both the above and are also dealers for Knots2U and can advise on the Gap Seals.

A and C
19th Jun 2007, 05:57
So far all we have is a lot of "mine is bigger than yours" in terms of numbers for the fuel burn of the PA-28.

Not one of you has stated the power setting used and with out this all the numbers are useless.
The fuel burn will stay constant with increase in altitude (but the TAS will increase) so flying high will save money and the rough altitude vs distance on this class of aircraft is 5000ft for a trip distance of 100NM with the best alittude to be for range being between 6-8000 FT.

A NON INJECTED O-360 Lycoming should be using about 36LT/HR at 60% power and 40 LT/HR at 75% power. You will have to read the POH for the RPM vs Altitude for your aircraft to get the RPM settings (these nunbers include taxi and climb and should work with a 2 hour leg).

Please remember anyone who tells you that XXXX is cruse RPM without quoting a presure altitude on a fixed pitch prop is talking rubish.

Most of the posts above show how few people have an understanding of the POH for the aircraft that they fly.

gcolyer
19th Jun 2007, 07:53
A and C

Get 100 PA28 archer owners in a group. Ask them the average fuel burn of their aircraft. I bet at least 80 of them say 40ltr and hour.

Which incidentaly 2 of us which again incidentaly specificaly talk about archers said 40ltr an hour. All the other posts are tangents including mine.

Now had the original question been "What is the fuel burn of an archer at 62.3% power setting at 5324ft" then your opinion would actualy be about right.

But I do agree the POH is the oracle as far as figures ar concerned, due to the fact that as demonstrated us pilots all have different opinions/views/ideas/answers.

Rod1
19th Jun 2007, 11:20
I operated an AA5B (same engine) and in real world operations, running consistently at 75% (altitude and temp corrected) she burned 40lph. This was with leaning the mixture for the cruse. Remember this is an overall figure, not the amount burned in the cruse.

If this is too much you could always get a more efficient aircraft…

Rod1

gcolyer
19th Jun 2007, 11:27
Yep I run an AA5-B as well, and she burns on "average" 40ltr and hour. And cruises significantly faster than the archer.

FougaMagister
19th Jun 2007, 22:45
Remember the POH mentions US gallons (not liters), so 10 USG/hr is a good ballpark figure, and one that I use whenever I fly an Archer (in good nick). Seems to work well when comparing fuel burn on the PLOG with fuel remaining at the end of the trip (the fuel gauges in the PA28 series being a bit approximative). Basically, with the full 48 USG, you can expect an endurance of 4 hours/40 USG (plus 5% contingency fuel and at least 30 minutes' fuel for diversion purposes).

Of course, leaning the mixture helps, provided you fly above 3000'-3500' or so - not something we get to do very often in this country!

Wheel fairings are supposed to provide a slight perf enhancement (in terms of fuel burn/airspeed) by reducing drag. But they also mean more maintenance if operating out of a grass airfield.

Cheers :cool: