starting engine

[caioatpl]

Hey!
Can someone tell me what do i do in case when i'm starting the engine of a C152 e the oil pressure indicator is not in the green arc? Should i wait or shutdown the engine?
And which are the situations it might happen?


Thanks,

Caio Nacimento

[Pugilistic Animus]

caioatpl It usually takes a few moments to get flowing if it remains too low for a greater period of time than the flight manual specifies -shut down

Always refer such questions to the Flight Handbook and for better details about things such as engine leaning---refer to the Engine manufacturers operating manual--as the engine company is different from the airframe company so that usually provides a more detailed answer than the flight manual this helps save fuel or engine maintenance or headaches...

Ho dimenticato quasi tutto di mi italiano perche faccia molto tempo allorche lo parlai ma riccordo un poco


Ciao...

[Big Pistons Forever]

How fast the oil pressure rises is dependent on the oil temperature. If the engine has just been running then the oil pressure should register almost immediately after the engine starts. However the hot oil will be thin so you will likely not see the oil pressure in the green. As long as it is above the lower redline at idle you are OK.

If the oil is cold there will be a delay before the oil pressure starts to rise, but the idle oil pressure will be higher as the cold oil is thicker.

Personally if I do not see oil pressure in 15 seconds on your typical small Lycoming or Continental engine, I would shut down.

[piperboy84]

as the engine company is different from the airframe company so that usually provides a more detailed answer than the flight manual

Interesting, I have always wondered about this, My POH says i should do run-ups at 2000 RPM, the engine manufacturer states that run ups be done at 1800rpm,

Not sure the difference matters but i do it at 1800rpm

[shumway76]

If there is a difference between the POH & engine manual, I'd follow the POH.
I think the engine manual information is more for workshop / overhaulers to follow as they work on the engines by itself.
POH is the related to both engine & airframe combination.

[piperboy84]

Silvaire1 Runup rpm may depend on the prop

Yes that is the reason, mine is a fixed prop and here is a cut and paste from the manual,

(Fixed Pitch propeEler). Aircraft that are equipped with fixed pitch propellers,
or not equipped with manifold pressure gage, may check
magneto drop-off with engine operating at approximately 1800 RPM
(2000 RPM maximum).

I still wonder why the POH says 2000, I fly from grass and dirt strips so i go for the 1800 to reduce the amount of crap i kick up

[Pugilistic Animus]

I lost one of my post here to cyberspace I don't recall what I had written before, due to Rum, but in brief, generally the AFM refers the reader to the engine manual for more details---the overhaulers use the maintenance manuals not the engine manufacture's

as previously mentioned the propeller's details are to be found in the propeller manufacturer's manual...so there is more than one way to peel a potato...but at the very least everything should be refered to the flight manual this is why I never discuss leaning or manifold pressure/RPM combos, plus much depends on options do you have CHT/EGT etc...always read the handbooks...they tell you everything!

edit: same advice as above goes for avionics or other instrumentation or pilot controlled STCs read the manufacturer's manuals...

[Jabawocky]

If there is a difference between the POH & engine manual, I'd follow the POH.
I think the engine manual information is more for workshop / overhaulers to follow as they work on the engines by itself.
POH is the related to both engine & airframe combination.

And when bot the engine and airframe manufacturer contradict them selves and each other what then?

And no I am not joking.

plus much depends on options do you have CHT/EGT etc...always read the handbooks...they tell you everything!

Well that is half true. It depends, a good EDM or similar, and some good education and you will be 100% better off than just following the POH for doing mag checks. In fact the methods in POH's really just prove the mags have not been stolen.

For those who have well equipped machines learn to use the gear, and even the JPI manuals are not quite perfect, although better than most.

For those who think doing the mag check full rich is the way to go. Think again. I have no doubt the knockers will arrive soon, so do your homework properly and seek the truth. Even in your C152 with no gauges. Tacho will do!

[Halfbaked_Boy]

It also depends on how good/bad/new/old the gauges and/or sensors are, it can vary wildly from aircraft to aircraft.

In theory if we don't see oil pressure rising within 30 seconds of start we should shut down, but in practice (on many of the battered old ruins of training aircraft nowadays), it could take until you're doing your power checks to see a decent reading. It can be helpful to ask the instructors familiar with that particular aircraft the question you've posed here.

Immediately after start, it's the starter warning light that's the BIG biggy.

[Pilot DAR]

If there is a difference between the POH & engine manual, I'd follow the POH.
.....................
POH is the related to both engine & airframe combination.

Very wise.

There can be differences and contradictions between engine and airframe manufacturer's manuals. In aircraft approved before the format of these manuals was well established (CAR 3 aircraft) the statement"... or as stated in the aircraft manufacturer's manual" was not always in the engine manual. Newer manuals generally have something like that. This should be taken as the "tie breaker" to direct you to the aircraft manual as the highest authority.

Other manuals can exist, and indeed supersede the aircraft manual, if it is approved by the authority. Be very cautious of the many other documents out there which offer all kinds of advice and instruction on operating engines. Some are useful, some not so much. If they are "approved" they will be associated with an STC or similar approval, and distinctly marked as such.

It is very likely that the national regulations governing the operation of aircraft state a requirement that the pilot operate in accordance with the "approved" manual(s) for the aircraft. That does not mean that you can't use extra wisdom you have, and perform extra checks and operations, but if those contradict or circumvent the approved information, you're on thin ice as the pilot if something goes wrong. No one's going to get upset if you mag check at 2000 RPM rather than 1800, but dramatic deviations and subsequent difficulties can attract unwanted attention.

In some cases, an operator wants to deviate from what the manual says. (Airlines sometimes do this). In such cases, they will usually obtain a Flight Manual Supplement from the aircraft manufacturer, or have their operation specifically approved by the authority. This is very rare for GA aircraft.

[Pugilistic Animus]

And when bot the engine and airframe manufacturer contradict them selves and
each other what then?

since the AFM generally refers one to the engine manual, for matters such as leaning...I'd generally use the engine manual, if I had it...in reference to my mention of CHT/EGT...I was indirectly refering to leaning... The more instrumentation the better it can be done from primative methodes of pulling back to getting a bit of rough running the going forward..or even just putting the mixture just so...so a complex scientific analyis sunject to endless hangar talk...of course for that I just follow the books which ever maybe available...just as each registrations has it'sown POH so does eeach engine...of course the flight manual alone is just fine
as far as mag checks I don't make a huge deal out of them I just do them at run-up as I'm told...I'm not that smart

As far as the different run-up RPMs between the manuals- on older well worn planes the needle[s] on the tach[s] is/are jumping too much to see the RPM drop so I'd use the higher RPM to smooth things out...and since my students probably wont use the engine book I just go with the POH figures ...If I owned the plane I would use the engine manufacturer's figures...

I know just enough details about the engine to get myself in trouble...so I have to use the available manuals...I think jet engines and the PT-6 and Garrett are easier than pistons...more clear cut...but I'm not teaching rocket engineering so I just do [and have my students do] what the checklist or POH says... We don't even have access to the engine manuals Louie keep those at his house they are his planes....

That being said I agree 100% with the above post...it takes some discretion and really understanding what's what to apply the engine/POH combo judiciously...one can never go wrong with the AFM/POH

[mad_jock]

Garrett are easier than pistons...more clear cut...

You have got to be joking.

SRL's on or off whats the limits for the day.

HAve you got nicads or concord batteries.

Is the GPU a plugged in job and the airport lights dim when you hit the start button or is it a plugged in job and the aircraft tries to rotate round the prop on start.

If a cart GPU does it turn the Apron IMC when you hit the button or does it just hum a bit more. Or is there a big bang when it drops out just after light up and you then have to fanny around with a vent run or jump out and spin the props. Both methods may involve 50ft of flame shooting out the back and scaring the crap out of anyone near by.

How near is the engine for coming off the wing and what state is the starter gen in.

There is huge variations in starts with garrettes.

At least with a donk the sod starts or it doesn't and you don't have to have a sixth sense to guess if your just about two write off quarter of a mills worth of engine.

[Pugilistic Animus]

Yes but there is very clear and unamibigous guidance with them in the AFM the turbocomander never gave me a problem...that's my only experience with Garrets...but when I said that I was really thinking of 'Big-pistons' especially when they have superchargers and turbochargers and such...none of which I ever got to fly...not bog standard Lycoming/Continentals...to me those big pistons seem real hard,...

turbines require just following what the course taught you...big pistons seem like black magic....USE a good GPU...don't go to the cheap FBO...

[mad_jock]

I said that I was really thinking of 'Big-pistons' especially when they have superchargers and turbochargers and such

Fully agree on that one.

With garretts each one is a lovely lady which you have to talk to to get the best out of. She can be a bitch some days and others an utter star.

MJ who has 4k hours and 9000 starts on garretts and best effort was a 60 ft blue flame out the back when I swung the props after pulling the red handle. Don't ask me how I managed it, I don't have a clue but was bloody impressed by the whoosh through the front and arse of it looking like concorde. ATC and AFS were less than impressed as was the ground crew that felt the waft of hot air over them or the bloke that was driving the baggage truck which it passed in front of.

Sitting in OAKN repeating 10% light up 40% oil light out please baby don't hang your a lovely lady. You don't have much choice in FBO.

[Big Pistons Forever]

Since we are completely off topic I have to note that starting a turbine is science with a lots of math and reference numbers which any monkey can rattle off, however starting a P & W R2800, particularly when it is hot, well that is pure art . But you can't congratulate yourself on one good start , you still have 3 more to do