Well, I totally do. Of course not from of aircraft flying, but sure from aircraft making superfluous noise when operating on the ground. Two particular hates:
1) engines momentarily revving up upon startup, to 1500 or even 2000 RPMs. Two out of three starts at your local airfield are of this kind…
2) people running at excessive RPMs when running their check lists, doing takeoff briefings on the ground. It’s actually very easy to hear which one is turning eccessive RPMs and which isn’t. 1000RPMs are more than enough. Even 800 or 900 are usually enough for a smooth idle. Most people run 1200 RPMs or even more.
One factor is that a lot of alternator installations won’t charge the battery if below say 1100rpm. The TB20 POH says 1200rpm for ground ops – this is too high for taxi however.
Why do you think you necessarily need the alternator to charge the battery during those few minutes that you spend on the ground? Lots of time whilst in the air…
Yes; a fair point.
Bosmanticic
I hardly think you an call someone who is abiding by a manufacturers SB “ignorant” , well informed would be a better description.
There may me some very experienced members of the two wing master race who can get the mixture perfect for all phases of flight ( & taxi) while not compromising lookout, taxi speed, and airfield navigation but the average rental pilot flys less than thirty hours a year so mixture adjustment is well down the list of things to do especially while taxiing so the lycoming shut down drill is required to assure engine reliability.
I don’t agree.
I think it’s easy, even for an “average” private pilot, to pull the mixture out an inch or two after vacating the runway. No precision needed. It only becomes difficult if you have never been used to doing it.
That SB is merley a poor workaround trying to solve a basic lack of engine management.
boscomantico wrote:
Why do you think you necessarily need the alternator to charge the battery during those few minutes that you spend on the ground? Lots of time whilst in the air…
For a short VFR flight I would not care.
For a XC flight and especially if IFR, I want to take-off with a fully charged main battery. Not one that will be fully charged 15 mins after take-off.
If I lose my alternator I like to know I have my 30 mins worth of avionics power, not 20.
On some large aircraft that use the main battery for emergency power (as I do) there is a take-off limitation that charging amps need to be below ‘x’ before take-off. I use the same for every IFR T/O.
I need 1150 rpm to avoid discharge with all avionics on, 1200rpm to properly charge, so that is what I keep at the holding point except for runup. I have a yellow caution that will warn me whenever charging 10 amps or more. My aim is to not get that warning during take-off.
I have never seem a discharge on my battery at 1000rpm.
So some most either have a struggling alternator/battery or are adding some high power consumers immediately after engine start.
Worth to look into
I support Boscomantico 100% in his observations at the airport.
High RPM starts and ground idle is totally unnecessary, and gives you away as someone that don’t really know engine management.
I lean to almost stumble after start up, then taxi forward by adding mixture. That is as lean as you can get.
For LOP ops, making sure your plugs are clean after ground ops is imperative.
And before I forget; You don’t have to warm your engine for 15 minutes just outside my open hanger door with 1800rpm to get into the green on your oil temp meter before moving to the holding area. It will roll just fine with 1200rpm to break loose, then you can wait for your temps somewhere else. THANK YOU
A_and_C wrote:
so the lycoming shut down drill is required to assure engine reliability.
Well… In my club we never follow that drill and we have never had any valve sticking problems either. We did have some very minor problems with lead fouling of the spark plugs which were easily fixed by running lean at full power for a short while during engine runup. After switching to unleaded fuel (91/96UL) some years ago that problem has gone away, too.
Our aircraft use Lycoming (I)O-360 engines.
Well as you use 91/96 unleaded fuel I would say thats the reason you don’t have any plug fouling or sticking valve problems. How its operated won’t have anything to do with it.
Same for those that lean aggressively but for those that don’t surely following the SB from Lycomnig would be the sensible thing to do.
