It always makes me grin at the thought that turning into the wind makes any difference to temperatures when doing a run up, surely the 200mph+ wind coming off the prop will keep the engine just as cool as another 10 knots of headwind. Even a push prop will suck sufficient air through the engine.

It always makes me grin at the thought that turning into the wind makes any difference to temperatures when doing a run up, surely the 200mph+ wind coming off the prop will keep the engine just as cool as another 10 knots of headwind. Even a push prop will suck sufficient air through the engine.

 

As long as there isn't a tailwind during run up, then any other position is fine. That keeps any exhaust gases and fumes from entering the cabin. 

Without leaning on ground you WILL foul your plugs. On a hot day in Aus, you run the risk of cylinder damage trying to un-foul your plugs at the run-up before take off from not leaning in the first place.

 

On a 30+ degree day, at a busy airport like YSBK, it's not always possible to point those engines into the wind while doing the run up and those CHT's can go through the roof if not careful.

 

This is one thing I do not really get. Why do you need to lean on ground in this plane? I am not a professional flyer myslef but I am 100% sure that all pilots I was flying with so far on a Piper Archer, all of them did not lean on ground. Is this simply because those Archers have another engine type? And even the manual says nothing about leaning on ground, but I already fouled my plugs after only 5h time on the Cherokee...

I think the "fouling the plugs" simulation is overdone.

The 140s I fly only go in every 100 hours and no one leans them on the ground and it's not part of the checklist. Most of the fouling, if it occurs, is burned off during the run up.

 

That's not to say there's not benefit to leaning on the ground. There is. But it's overdone in this case.

Plugs will become fouled without proper leaning, even on the ground.  This has happened to me and others in real life.  Just because you are at sea level, density altitude may be well above 3000', especially in the summer.  Density altitude is the airplane 'thinks' it is at based on non standard temperature and pressure.  Part of a good preflight is to determine pressure altitude and density altitude. (this knowledge is critical when flying in mountain areas)  Use Density altitude when using the take off distance, climb, cruise, landing charts as well.

 

If your engine 'feels' it is above 3000' ft and you don't lean the mixture, you will have fouled plugs for sure. 

 

To figure Density alt, first you must calculate pressure alt.  Lets say current altimeter is 30.12, field elevation is 1200' and temp is 30C. 

30.12-29.92=.20

.20*1000=200

1200-200=1000

 

Pressure alt is 1000'

 

Now use an E6B or density altitude chart to find your density altitude using pressure alt and temp.

http://www.asiresource.com/DensityAltitudeChart.PDF

 

1000' @ 30C ~ 3000'

 

This is why you must lean on the ground

Why do you need to lean on ground in this plane?

 

 

Leaning on the Ground (AvWeb) By John Schwaner, Sacramento Sky Ranch

Good, I will keep that in mind. I really never heard of, so when I will start my PPL course (sooner or later), this is certainly something to remember.

For $50 the immersion is incredible. This aircraft is closer to the r/w aircraft than any sim aircraft I have flown. But it is a ga aircraft and a trainer aircraft. If you are a big iron person or are a person that likes speed this is not your aircraft. But if you are a person that appreciates flying at the steam gauge level you can't find a better and more realistic aircraft to do it in than this one.

For $50 the immersion is incredible. This aircraft is closer to the r/w aircraft than any sim aircraft I have flown. But it is a ga aircraft and a trainer aircraft. If you are a big iron person or are a person that likes speed this is not your aircraft. But if you are a person that appreciates flying at the steam gauge level you can't find a better and more realistic aircraft to do it in than this one.

Any help would be greatly appreciated.

 

I purchased the Cherokee from A2A,  By far this little plane is my favorite, nothing I have bought comes close to this.

 

I have learnt to start plane,  taxi and take off pretty good, well for me anyway.  Im also pretty happy with the leaning thingy.   Even learnt how to use them Autopilot, heading bug and have found all my secret buttons for controlling Gps and autopilot.  

 

I set up a flight from Sumburgh Scotland to fly in the Ireland direction, didn't really mind just wanted to fly..  Spent ages setting up everything.  Just as I got past Fair Isle Airport,  without any warning, my engine died back to 950/1000 RPM,  I had no control over throttle,  so basically it was like my throttle cable snapped,  my RPM just sat at 950/1000.  I eventually made a big splash.   I don't know what happened

 

My left tank was full my right tank was just over half full, my fuel selector was on right tank,  so plenty of fuel there. 

At the time of incident I was at full throttle.

My engine was leaned to 59%

 

Any idea's

I fly Archers II and III at my school. Ill tell you in the winter time I want the mixture leaned. I have seen it where the fuel is cooling the engine so much that it takes a very long time for the engine to "warm up" and you can even hear it struggling to stay alive during the first few seconds. If the mixtures is leaned it will warm up faster and the heating will also be available sooner after take off. Comes in handy at 17F in PA for the past few weeks.

Any idea's

 

 

Hi Elaine,

 

Sounds like carb ice to me.

 

If you notice a drop in rpm, carb heat should be turned on.  There's a couple other items to hit, like turning on the boost pump, switching tanks, checking mixture etc.

 

Btw you did a preflight? Also, right after preflight, I like to check the Maint. Hangar.

 

-Rob

I did most of my single flying in Archers and Warriors, and to be honest I never had any issues with engine temp, but then again, I don't think a basic PA28 is installed with CHT gauge...

 

It wasn't until I started to fly twins (which all had CHT gauges) that I realised how critical pointing the engines into the wind while doing run ups was. It did vary between aircraft types, and even same types but different rego's, but I found that in general if OAT was above 25c then you better turn into wind for run ups. You can even see a diference in CHT temps if you are parked at an angle to the wind. The upwind engine will be a lot cooler.

 

With the leaning on the ground -  The 100LL is a high octane fuel. I think at full rich mixture it is close to an octane rating of 130, and 110 when leaned... What this means is that it requires a higher CHT to burn efficiently. At low temps (at idle) it doesn't burn properly and causes a lead build up fouling the plugs. Of all the different types I have flown, all required leaning. I found with the Warriors, tomahawks, duchies, partenavias etc all required about 65% mixture on ground. depending on the weather, as low as 50% mixture.

 

Diego

So, what happened to Poppet was improper leaning while on the ground which caused fouling in the plugs?

So, what happened to Poppet was improper leaning while on the ground which caused fouling in the plugs?

 

No - I'm with Great Ozzie on this one. The symptoms described by Elaine sound most like carburettor icing. I must admit I didn't know much about this phenomenon until flying the A2A Cherokee, but I learned a great deal from this thread on A2A's forums.

 

As well as the temperature 'danger zone' for carb icing (well illustrated by the graph in this post by 'ft') one other thing I learned from the discussion was that carb heat should be either fully on or off. Partial carb heat application can actually make carb icing more dangerous!

 

I'll confess I've been deliberately flying the A2A Cherokee in conditions conducive to severe carb icing (e.g. temp and dew point of around 5 to 6°C) to experience some of the simulated 'Accu-Sim' effects. For example, carb icing with high (cruise) RPM as Elaine describes is certainly possible, and it can start of as quite a subtle and insidious power loss. On the other hand, selecting full power after a descent at idle can result in... Well absolutely nothing - no power at all - until carb heat is applied.

 

Of course, improper leaning on the ground can foul the spark plugs, but this will generally be cleared up by running at reasonably high RPM for a while. In other words, if you survive the take-off and climb out with fouled plugs, you'll probably be okay.

 

By far this little plane is my favorite

 

I couldn't agree more!  :smile:

 

Cheers,

Nick

 

 

On the other hand, selecting full power after a descent at idle can result in... Well absolutely nothing - no power at all - until carb heat is applied.

 

Since the carb heat uses heat from the engine, it's possible that if the engine cools off too much during a long descent at idle, applying carb heat can result in...Well absolutely nothing - no power at all...

 

Yikes!