My close call

[Nightmare]

Recently, I had just had a 25 hourly service done on my Jabiru LSA-55by a local L2 at a local aerodrome. An oil and filter change mainly. I also had some other minor jobs done that were unrelated, a tire replacement, and some fiberglass patchwork. It was the first time since I purchased the aircraft that an L2 looked over it.

 

Anyway, after the service, I taxied her out to the runway, the L2 asking me to just keep an eye on the oil pressure gauge. All was good, it was reading a nice solid 4 in the green.

 

I took off with nothing out of the ordinary, I continued to monitor the oil pressure, normal, stayed at 4. I entered the downwind leg and started thinking of departing the circuit. It was then, I smelt smoke, looked down and saw smoke in the cabin, looked at my instruments and saw that my oil pressure was now reading zero, it was reading a steady 4 only a few seconds earlier.

 

I was at the base turning point, so things happened quickly, I discarded all chances of exiting the circuit, and committed to landing back at the aerodrome I just took off from. I throttled back to idle, turned base and made my base call. I came in for a glide approach and landed with no incident, exited the runway and shut down as soon as possible. I got out and saw oil flooding down the front wheel.

 

I didn't call a pan pan or mayday, as the smoke dissipated when I reduced power to idle, and I didn't lose engine power or performance. To be honest, I never thought I was in any danger given my proximity to the aerodrome. Once I made the decision, thanks to my training, it was all automatic, engine to idle, get the plane heading to the field whilst lowering the nose for best glide and land her. I think my instructor would've been proud of my performance, it was just like my EFATO training.

 

But yes I reported it to RAA as an incident.

 

The culprit: a split oil hose near the oil filter. Last time it was replaced, 3.5 years ago, required replacement time: 5 years. Possibly a faulty hose. The L2 replaced the offending hose, plus one beside it, and refilled the oil.

 

I flew her back to my home field with no further incident.

 

I praise the quality of our training, it paid dividends for me. Mind you, if that hose blew further away, I wonder how long I had till I had an engine failure? Now that would've been a pan pan situation.

 

Tony

 

 

[fly_tornado]

is the oil cooler pressurised by the oil pump in Jabirus?

 

 

[Nightmare]

is the oil cooler pressurised by the oil pump in Jabirus?

I don't know know FT, maybe someone else on here could answer that one.

[DGL Fox]

Yes you did well Tony and you got yourself and the plane down safely.... :)

 

David

 

 

[poteroo]

Well done.

 

Moral of this story is: after maintenance, always 'test' fly your aircraft for at least 10 minutes - keeping it within gliding range/altitude of the strip.

 

happy days,

 

 

[Nightmare]

You would be able to tell if the oil hose in question was under pressure or just a return line by seeing what sort of fitting it has at the end of it, both ends if visible. If it's just a worm drive type clamp it won't be under any real pressure. If it's a fitting as in a spanner needed to remove then it's a pressure hose. Lucky it happened whilst still in the circuit. I wouldn't be too concerned about a distress call, aviate navigate communicate in that order, you did well, fly the plane priority No 1:-)

It must've been a non-pressurized return line, it was a rubber hose fitted over a lug, held on with a standard hose clamp, appearing to be the type commonly used to hold on radiator hoses on cars.

[aro]

Jabiru are a wet sump engine aren't they, so I would expect all oil lines to be pressurised.

 

 

[Kununurra]

Well done on a safe landing.

 

Out of curiosity did you ask the L2 why he suggested you watch the oil pressure gauge? Or was it a general comment due to the hrs the aircraft has done.

 

I understand that monitoring gauges is a never ending task not just oil pressure.

 

✈️ Cheers

 

 

[IBob]

Yes, well done on the landing.

 

Though both the timing and the nature of the fault must raise a number of questions?

 

 

[frank marriott]

From the maintenance manual (2 yrly NOT 5)

 

8.4.1 Flexible Hoses

 

 All flexible hoses in the engine compartment should be replaced at engine overhaul or every 2 years whichever comes first. Hoses which show visible deterioration (cracking, excessive hardening) should be replaced immediately, irrespective of age.

 

 

[Nightmare]

Yes, well done on the landing.Though both the timing and the nature of the fault must raise a number of questions?

I'm sure those questions may be raised and investigated due to my report I did to RAAus.

Well done on a safe landing.Out of curiosity did you ask the L2 why he suggested you watch the oil pressure gauge? Or was it a general comment due to the hrs the aircraft has done.

I understand that monitoring gauges is a never ending task not just oil pressure.

 

✈️ Cheers

He said that it was just something to watch as the new oil settling into all the leads and other places that a running engine would make the oil go, or words to that effect. He also advised me to check the level when I got back to my home field, and said I'd probably need to top it up a bit for the same reason.I tell you, this event shook my confidence in flying a little. However, I did a couple of circuits the next day.

 

Cheers

 

Tony

 

 

[Nightmare]

From the maintenance manual (2 yrly NOT 5)

8.4.1 Flexible Hoses

 

 All flexible hoses in the engine compartment should be replaced at engine overhaul or every 2 years whichever comes first. Hoses which show visible deterioration (cracking, excessive hardening) should be replaced immediately, irrespective of age.

I would've thought L2's, not just the one I used, but the other 2 different L2's who were servicing the aircraft would've picked up on that.Interesting that the manual states the word "should" and not "must"

 

 

[alf jessup]

Well done Tony

 

Training pays off, you handled it well and have learnt from it

 

I had a STING (Sh!t This Is Not Fun) moment back in October last year which eventually was diagnosed as carby ice

 

Almost put down in a paddock from 2500 ft when it started before it cleared up, initially I thought I lost the tip of my prop the vibration was that bad

 

Training a practice paid off for me in that event

 

Certainly gets the adrenaline happening

 

 

[SSCBD]

Well done on a safe landing.Out of curiosity did you ask the L2 why he suggested you watch the oil pressure gauge? Or was it a general comment due to the hrs the aircraft has done.

I understand that monitoring gauges is a never ending task not just oil pressure.

 

✈️ Cheers

It is usual to watch oil pressure with oil filter / change. Common sense. Same as any change to radiator hoses / fuel lines /filters etc etc.

 

 

[Yenn]

recreational aircraft do not necessarily have swaged fittings on oil pressure lines. I have hose clamp fittings on al my lines in the corby. The engine comes with those fittings.

 

The oil lines are pressurised on the Jab engine, they go above the oil level in the sump and are not suction lines to the pump.

 

 

[Nightmare]

Well done on a safe landing.Out of curiosity did you ask the L2 why he suggested you watch the oil pressure gauge? Or was it a general comment due to the hrs the aircraft has done.

I understand that monitoring gauges is a never ending task not just oil pressure.

 

✈️ Cheers

I guess I also told him this was my very first service in my first aircraft that I purchased at the end of February this year.

[facthunter]

I don't know how long the engine operated without oil pressure. The type of bearings used in those engines don't tolerate much running with NO oil pressure. Perhaps a filter opening for metal check? I'm very fussy when it comes to engines in a plane but always consider an engine failure a possibility, even IF remote. You make your own luck to a great extent. Owning your own plane gives you more control over what you have to accept if you hire. Nev

 

 

[Nightmare]

I don't know how long the engine operated without oil pressure. The type of bearings used in those engines don't tolerate much running with NO oil pressure. Perhaps a filter opening for metal check? I'm very fussy when it comes to engines in a plane but always consider an engine failure a possibility, even IF remote. You make your own luck to a great extent. Owning your own plane gives you more control over what you have to accept if you hire. Nev

The time it took from the start of the base leg to landing it. As soon as I saw the pressure at zero, I set the power to idle, and made the turn, attitude to best glide. As soon as I was near taxi speed, I was exiting the field and shut down as soon as I was just off the taxiway. It felt like seconds, but it was probably between 1 and 2 minutes. I couldn't have had a better place for this issue to happen, being at the end of the downwind leg, except maybe on the ground...Tony

 

 

[Nightmare]

I'm not planning on doing any big XC flights for a little while, until I am confident everything is good, and I think it is. I went for a couple of touch and goes the day after the incident and all was good.

 

 

[Geoff13]

I concur with facthunters comment.

 

I would be doing a filter cut and check at 5 hours then if it is ok another one after another 20 or so.

 

It could pay to fit a very strong magnet to the outside of the filter for a service cycle to help with that check.

 

I would be doing all of my flights up until that 20 hour check within glide of a suitable landing area. It can be boring but could be worthwhile.

 

 

[Nightmare]

I concur with facthunters comment.I would be doing a filter cut and check at 5 hours then if it is ok another one after another 20 or so.

It could pay to fit a very strong magnet to the outside of the filter for a service cycle to help with that check.

 

I would be doing all of my flights up until that 20 hour check within glide of a suitable landing area. It can be boring but could be worthwhile.

Cool, I'll have a chat with a LAME about this. I'll be doing this within the next few days.

[Geoff13]

Oh by the way well done on the safe landing.

 

I honestly do know what it is like to have smoke in the cabin, refer to my post on Incident 13 May (was that really 2 years ago) and I know the effort it takes to fight off the panic.

 

So seriously well done on that point.

 

 

[Nightmare]

I don't know how long the engine operated without oil pressure. The type of bearings used in those engines don't tolerate much running with NO oil pressure. Perhaps a filter opening for metal check? I'm very fussy when it comes to engines in a plane but always consider an engine failure a possibility, even IF remote. You make your own luck to a great extent. Owning your own plane gives you more control over what you have to accept if you hire. Nev

 

I concur with facthunters comment.I would be doing a filter cut and check at 5 hours then if it is ok another one after another 20 or so.

It could pay to fit a very strong magnet to the outside of the filter for a service cycle to help with that check.

 

I would be doing all of my flights up until that 20 hour check within glide of a suitable landing area. It can be boring but could be worthwhile.

I had a real good chat with my L2 about these issues, and re-read the emergency procedures for loss of oil pressure in the POH. The procedure says: "Reduce power to minimum to sustain level flight and proceed to nearest landing area"My L2 said that all engines are designed to run on no oil for short periods, ie, during engine startup and warm up. Also, all the moving parts at the time of the hose bursting were well lubricated, so my immediate action of idling the engine for the rest of the flight, and the fact that this was only for about a minute or two, the time from base to engine shutdown just off the runway. He doubted any damage would have been done. Plus I have been doing a few hours flying since then with no perceivable problems. In fact, she has been running better since the hoses were replaced in my opinion. He will be doing an inspection of the oil filter at the next 25hourly, and he has offered to send away an oil sample for analysis for a small extra cost, may be worth it!

 

I have to admit though, this incident has shaken my confidence a bit.

 

 

[facthunter]

Some older engines had a fair tolerance for intermittent oil supply they tended to have babbit lined bearings. a fairly soft and low friction coefficient material. It was taught after inverted flight, to idle the motor till the pressure ceased fluctuating as air gets into the system when inverted unless you have a special Designed Inverted oil system.

 

More modern bearing materials are copper lead with an indium overlay (if you are lucky), or alutin. These materials run more clearance, mainly to allow more oil to flow to cool them as they have a higher coefficient of friction and generate more heat and can be quite a lot more noisy without oil to cushion the mechanical noise. Motors should be pre pressurised before initial ground run.. I don't believe these motors can be assumed to be OK for a small time. Under full load most fail almost instantly with any air in the oil system.

 

I have already said I would remove the filter and open it. Small price to pay for a check. You operated within the directions issued by idling quickly, but no one can say they are designed to operate for a while without oil. They do have to put up with a reduced oil supply at cold start but it gets a partial flow rather quickly and may even have enough on the starter if it doesn't fire instantly. You don't operate above idle till the pressure stabilises at a given figure. Whether there's any damage is speculation that I won't add to. Metal in filters is used as a condition check on MOST aircraft, even jets where a high oil pressure is also a problem as they spray oil onto antifriction bearings. Some new engines show particles that can come from machining of the original components and should have been removed by a process before assembly but some burrs may exist and the filter should catch them.( That's what it's for). If the filter's clear I wouldn't waste money on an oil condition check, but continue to open the filters. I would do that every time actually. Magnets will only attract ferrous metals Ie some rings steel/iron bores and crankshaft, gears chains oil pump rotors or very usefully ball and roller bearings breakdown where used etc You need some training to interpret particles in a filter, but it's much commonsense applied. I usually run a strong small magnet over the bits trapped. Nev

 

 

[dlegg]

 

You might consider this modification to your plane. You will not have the problem you just had again.

 

Oil cooler lines.jpeg.pdf

 

Oil cooler lines.jpeg.pdf

 

Oil cooler lines.jpeg.pdf