The aircraft that I fly (Arrow with an IO360) and most others that I’ve flown COULD be taxiied full rich. It will eventually produce a problem, but not after one taxi.
There was one aircraft that I rented in the US, that unless agressively leaned for even the shortest of of taxi, would result in fouled plugs.
I can never get an EGT reading off the stop at taxi RPM. So I just lean until the RPM starts to die, and then enrichen it a bit so that it runs ok. ie No wasted fuel. It also helps the engine warm up faster.
I’m in no way an expert here, but in the odd occasion that I’ve got an aircraft with fouled plugs, only ever one set was fouled. So it would run smoothly on one set of mags, and rough on the other. If in this case, it was running rough on both, then either both were fouled, or the problem is something else. In either case, there isn’t a lot the pilot can do about it at this stage. If there is no combustion in the cylinder, there is no way to remove the fouling other than taking them out, which most renting pilots (including me) won’t know how to do.
As for if you could have prevented it, that comes down to what it is. If it was fouling then more agressive leaning would have prevented it.
If one plug is fouled, you can clean by running high power and agressively leaning.
If both are fouled, then you’re out of options.
If you can’t start it now, then it’s either both plugs fouled or something else, and you’re relient on engineering support. All you can really do now, is try again later to start it, in case it was flooded. (The excess fuel will evorape in a short period of time, so you can try again now).
The aircraft that I fly (Arrow with an IO360) and most others that I’ve flown COULD be taxiied full rich. It will eventually produce a problem, but not after one taxi.
True of course. As a renter, sometimes, there is little you can do. You have to live with all the little problems left behind by other (sometimes very low profile) renters. Other “classics” include: overtightened oil caps, messed up GPS settings, messed up audio panels, tyres with flat spots due to lock-ups on landing, etc.
Still, if this (severely fouled plugs, which is what we presume right now) happens on your return flight, then you probably had the chance to make for a better outcome.
IME, every case of a fouled plug (several) was a bottom plug, never a top one. A real bugger because access to the bottom ones needs the cowling removed, which needs the prop spinner removed (unless you are a Grade A bodger and the customer will not notice the damage).
Unless you own a proper airplane you mean? No problem to access both plugs on any Cessna. My old 172 required a lot of screws to be removed and you could not open/close the cowling with the engine running. In the 182 there are camlocks and it’s easy. Actually I remove both cowlings on each stop on longer trips to check that everything is clean and tight. I’ve made some discoveries in the past so it’s become a good habit.
Short question here, not the main point of discussion: I find it ambiguous who to call first at Hamburg if departing VFR from the eastern stands of Apron 2 – see plate below. Do you call up tower directly as this area has been assigned to TWR? Do you taxi on your own to the green border and call Ground?
In my jepp
under 3.1.1.1 General:
Pilots shall request start-up clearance from Ground. On initial radio contact the respective apron designation shall always be indicated. ….. Pilots will receive instructions to establish contact on the frequency of Apron
under 3.1.1.2 General Aviation Aprons:
On initial radio contact the taxi lane should be indicated additionally.
I’d just call ground.
Pilots shall request start-up clearance from Ground.
Still ambiguous:
Start-up clearance for VFR? When I did that once in EDLV because it said so in the AIP, they told me that’s only for IFR.Indeed the national AIP for EDDH says:
12.3.2 Departing Aircraft
For departing aircraft (IFR) parked on apron 2 or 4, clearance for starting the
engines shall be obtained on the frequency of HAMBURG GROUND. On initial
radio contact, the respective apron designation and taxi guide line shall always
be indicated.
I also find:
9.2 Use of the aprons
Aircraft are allowed to use the aprons only with permission from FHG Apron
Control and on its instructions. Permission for the use of aprons is issued by
FHG Apron Control via radio or telephone and by the assignment of follow-me
cars. Use of aprons by aircraft is always subject to prior permission from FHG
Apron Control.
And:
10.1 Taxiing of aircraft on aprons 1 and 2
10.1.1 When taxiing, aircraft shall maintain permanent radio contact with
HAMBURG APRON. Instructions to change frequency shall be complied with
immediately.
And the AD chart says the area I park in is delegated to TWR (see screenshot above).
EDLV aha, the big Ryanair international airport. I think they have no Ground frequency there.
I’d still talk to Hamburg Ground.
On other airports this may vary, but I would always look into the AIP/Jepp.
Amsterdam has an own start-up frequency. There are many different ways to get into the airport system.
Don’t get scared from a small regional airport with attitude issues.
Starting on one mag results from Piper being a bit cheap and installing one mag with no impulse coupling. There are techncial arguments to use either one or two impulse couplings but Piper was generally convinced by the least expensive option.
The solution to plug fouling is REM37BY spark plugs, which were developed to solve that problem on O-235 Lycomings. I have no idea why they aren’t used universally on engines for which they are applicable. I’ve never had a fouled plug with them on my O-320. I also pull out the red knob when taxiing.
Both my planes have complete access to all spark plugs (or to have a look around) in 10 seconds. I never liked the idea of a plane that didn’t allow you to look the whole thing over before flight.
Patrick, hope you get the problem fixed!
The solution to plug fouling is REM37BY spark plugs, which were developed to solve that problem on O-235 Lycomings. I have no idea why they aren’t used universally on engines for which they are applicable.
Would it be permissible to use them on aircraft where they are not mentioned in the maintenance manual? Fine wires are better, too. I use traditional Tempest, can replace them many times for the cost of fine wire and when always going peak EGT, fouling is no issue.
Would it be permissible to use them on aircraft where they are not mentioned in the maintenance manual?
If they are PMA’d for the engine, I believe yes. The PMA would in that case be based on ‘fit, form and function’ as opposed to "identicality’. The Champion catalog is pretty comprehensive Catalog and (also FWIW) I believe REM37BY equivalents are available from Tempest – just put an extra U in front of the part number.
