Mixture rich on approach?

455 Bravo Uniform

455 Bravo Uniform

Final Approach
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Just flew with a pilot who on approach I asked him didn't he want to go full rich before landing? He said no, he'd just firewall it along with throttle and prop if we needed to go around. Does anyone else do this?
 
What was the airport altitude?
I n Florida, I go full rich for landing. Denver? Maybe not.
 
+2 on the yes. I don't go full rich unless I'm going around. Only takes a nano-second to do it. Same with the prop. I usually leave it at cruise setting unless I need a steeper descent. It all goes forward on a missed. I know there are a lot of Mike Busch haters on here but that's how he operates his twin cessna and his engine's are more than double TBO.
 
In Utah with base elevation of 4600 - 6000, I don't use full rich really ever. I lean for altitude at run up then take off at that mixture. Better performance and reduced wear and tear.


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Radar Contact said:
+2 on the yes. I don't go full rich unless I'm going around. Only takes a nano-second to do it. Same with the prop. I usually leave it at cruise setting unless I need a steeper descent. It all goes forward on a missed. I know there are a lot of Mike Busch haters on here but that's how he operates his twin cessna and his engine's are more than double TBO.
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+3
 
Having an all-cylinder EGT/CHT, even on a carbureted four-banger, is a huge help. Flying from a cool-weather, sea-level airport I learned that on takeoff in my airplane, the #3 (hottest) cylinder would stabilize at about 1290 degrees on climbout with mixture rich on a standard sea-level day. As I climb to altitude, I just progressively lean it to keep it at that same 1290-degree "happy place" all the way up. If the CHTs are where they're supposed to be, everything is great.

Before takeoff above about 3,000' density altitude, I'll pull out the mixture knob to more-or-less what it normally looks like when I'm climbing through that kind of altitude. Once I'm off the ground and the EGT stabilizes, I fine-tune the #3 cylinder to 1290 degrees. It's usually pretty close already, and a lot smoother and more power than arbitrarily taking off full rich.
 
Since the 'Kota is boosted it gets full Rich on short final as called for in the AFM. The consequence of possible full throttle operation without full rich outweigh the minor possible benefit of operating lean for a few more seconds. It has fine wire plugs so possibility of fouling is minimized.
 
When landing, I set the plane up in the pattern for a go around, which, if necessary, is leaned for takeoff. And that depends on altitude. Follow the POH yes, but most POH don't have leaning for altitude takeoff.
 
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455 Bravo Uniform said:
Just flew with a pilot who on approach I asked him didn't he want to go full rich before landing? He said no, he'd just firewall it along with throttle and prop if we needed to go around. Does anyone else do this?
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I know some teach this procedure. It really depends on the flight profile and aircraft involved. I had one client that insisted on doing it this way. He finally decided I wasn't full of **** when both engines quit on a visual approach. As with many things in aviation a little common sense goes a long ways. That and reading the manufacturers recommended procedures
 
900 feet here. Full rich, prop forward, and carb heat off (if it was on) on short final. Earlier than that and the engine pops too much because of all the unburned fuel.
​
 
This is one of those LOP koolaid thingys....


remember......G-U-M-P s?
 
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The only time I enrichen from cruise when landing at a sea level airport is if I have done a long decent from a high altitude. Below 5,000 feet I don't mess with the mixture lever.

Going full rich on approach has claimed its share of lives at high DA airports.
 
Sac Arrow said:
The only time I enrichen from cruise when landing at a sea level airport is if I have done a long decent from a high altitude. Below 5,000 feet I don't mess with the mixture lever.

Going full rich on approach has claimed its share of lives at high DA airports.
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And I feel I just learned something...Thanks
 
Cap'n Jack said:
And I feel I just learned something...Thanks
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I've been at 10,000 foot DA departures at KTVL in a Deb and a Turbo Arrow where the engine wouldn't even idle at full rich. In the Debonair, the fuel flow gauge has a setting in thousands of feet where you start lean, go full throttle, and enrichen to the altitude corresponding with the needle, which approximately gives you best power. In the TA, you advance the throttle and the mixture to full simultaneously, and by the time the engine and the turbocharger spools up you are good to go. And there are other methods of determining and achieving best power as well.

But you do have to be mindful as well on long decents to pay attention to mixture. The penalty to pay is that you end up too lean. That stung me one time, I was flying my Arrow II on a hot day, and I descended from 7,500, and around 3,000 feet, I started losing power. I pointed my airplane for the best field immediately (Watts Woodland airport, doable if I had a failure) and went through the checklist. And it was indeed mixture. I normally run LOP, and my engine runs fine LOP with no noticeable roughness. I pushed the mixture forward, not full, but forward, and there I was developing full power again. Whew.

That said, an overly lean condition is usually easier to recover from than an overly rich. Your engine usually doesn't suddenly quit from being too lean, it just doesn't make enough power. If it quits from being too rich, you both have a flooded engine condition, and probably fouled plugs as well to recover from. It takes more time. Sometimes too much time.
 
coloradobluesky said:
When landing, I set the plane up in the pattern for a go around, which is leaned for takeoff. And that depends on altitude. Follow the POH yes, but most POH don't have leaning for altitude takeoff.
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I agree. On approach you should be set up for a takeoff/go around scenario. My home field is at 6000 MSL, as are many of the fields I fly to. Full rich just doesn't work well.
 
Depends on the engine and the density altitude, but normally enriched enough for a go around, but that does mean full rich.
 
I leave the mixtures leaned and the props at cruise RPM. No need to foul the plugs and make a ton of noise both onboard and on the ground by going rich and high RPM. It's a non-issue to firewall it all in a go-around.
 
My home field is +25 feet and I normally fly between 1500 and 3500 feet. I start to lean at 3000 feet, works for me. Engine 4 banger 0-320 no EGT.
 
455 Bravo Uniform said:
Just flew with a pilot who on approach I asked him didn't he want to go full rich before landing? He said no, he'd just firewall it along with throttle and prop if we needed to go around. Does anyone else do this?
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I've heard of that practice, but the logistics of doing that in my plane would be a bit tricky for someone like me with small hands. I prefer to enrich, and to push the prop in, at the same time when descending from pattern altitude (usually earlier on an instrument approach, typically right after bringing the gear down at GS intercept or the FAF).

I really don't want to have to worry about anything but the throttle if I have to go around, or missed.
 
Up here, the 182 isn't full rich for takeoff so it isn't full rich on approach either.

It would blub and sputter and carry on like a moonbat on Facebook like it was going to die, with a combo of full rich and carb heat.

Definite nope. I just twist it back up to about where it was for takeoff on the way down from cruise.
 
MAKG1 said:
FTFY.

I occasionally see 3000 DA at sea level airports. Fresno on a hot summer day, for instance.
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True; DA is the important issue. But 3000 vs sea level is not that big a factor. I'd still be full rich on takeoff and landing. But DA of 9,000 (at an altitude of 5,000) would make a difference.
 
JOhnH said:
True; DA is the important issue. But 3000 vs sea level is not that big a factor. I'd still be full rich on takeoff and landing. But DA of 9,000 (at an altitude of 5,000) would make a difference.
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Depends on the airplane. Cessna singles lean above 3000, and it makes a real noticeable difference on takeoff. Pipers lean above 5000.
 
I think it's pretty much personal preference, to be honest. I almost always just leave the mixture where I had it in the descent, props at their cruise/descent setting, and sync on, but a guy I fly with often (and respect) always likes to push up the props, turn off sync, and go full rich on final (my bird is turbocharged, so there's no leaning at altitude except to pull mixtures back a bit on high-altitude rollouts to keep the engines from dying on the runway).

That said, in really crummy conditions, I'll bring the props and mixture up just to make workload less on the missed (although I'm still going through the motions of cramming everything forward regardless). There's a solid argument for doing things the same way every time, though, so like I said, I think it's preference.
 
If there's ever a mishap the first place the Fed lawyers will go is the POH procedures.
Not sure what yours says.

Just sayin'
 
My prop is set anywhere from 2,000-2,200rpm across the threshold with the mixtute set for peak EGT. Ive had to throw everything forward in a go-around. Not a big deal.
 
Jozu said:
In Utah with base elevation of 4600 - 6000, I don't use full rich really ever. I lean for altitude at run up then take off at that mixture. Better performance and reduced wear and tear.

Where in Utah? I'm flying from South Valley.


My instructor has us full rich for all phases except cruise. C172 180 hp fixed pitch.


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I have read mike busch where he says the only time you should be full rich is start up and climb below 3k feet unless high DA airport. I have tried leaving it lean during approach but my instincts always have me richen it. Ive tried both but my brain says full rich. As soon as wheels touch down and I slow to taxi speed I lean aggresivly.
 
korben88 said:
My instructor has us full rich for all phases except cruise. C172 180 hp fixed pitch.
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Hm. U42 = 4600' MSL elevation. Even on a 65 F day, density altitude > 6000'. It's the CFI's call, of course, but I'm not a fan of partial-power takeoffs in my C-172N/180 hp.
 
On approach, no. At the FAF or downwind mid field, yes.
 
Only time my red lever is full forward on my Cherokee is during engine start. Lean for taxi, lean at run up and lean again above 5000'.

My mechanic smiles when he looks at my spark plugs.
 
Timbeck2 said:
Only time my red lever is full forward on my Cherokee is during engine start. Lean for taxi, lean at run up and lean again above 5000'.

My mechanic smiles when he looks at my spark plugs.
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You lean even on hot summer days down in Tucson? Seems like it would be better to have the cooling from running full rich?

When I was doing my PPL in the 172 at Scottsdale we always leaned for taxi and takeoff, but some people seemed to always recommend full rich if you were below 3000'
 
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