oil pressure

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Lesson 23 – 6th August 2009 – 1440 – 50 minutes – Total so far – 25 hours 14 mins

Thursday, August 6th, 2009

Gorgeous weather today. I had, in my mind, an idea of what today’s lesson was going to be, namely some low level work (quick stops, autos and the like). It wasn’t to be, but I thoroughly enjoyed the alternative.

Steve suggested to maximise the weather and get a solo cross country in – Alnwick and back. Winds were mostly easterly and light – Runway 07 in use.

I plotted the course, and Steve went through the routing and features, which was helpful. 14 gallons of fuel required to allow for delays, taxi’ing, and I left with about 19 on board, so I was good to go.

I decided to use my iphone as the nav plan. It allowed me to easily time the legs and see when I should be arriving at the end of each leg.

Once we’d filled her up, we moved her well away from the bowser and other aircraft – a wise move !!! Actually, we’d have been ok for the liftoff, not so sure about the return bit though, but more on that later.

Permission to taxi to Foxtrot was granted with the clearance and I was asked to hold, which I did into the light wind. My first thought was to put it back down again on the ground, but then I thought that a bad idea as it’s good hover practice. After about a minute of waiting, I realised that I’d cocked up one of my checks. The door was open (my door). So, I had to put it down to close that. Silly me – done it before too. Need to ensure I do the checklists and don’t get carried away with the excitement of being solo.

With the door shut, Tower were on the blower asking me to perform a northerly departure straight away as they had an inbound. I was ready and I was off :-)

2300 feet was the intended altitude and i’ve realised that if I want to hold a certain altitude and I concentrate on it, I can do it, but when I want some sight-seeing or to check the map, then it can drift off.

With only me in it, I was maintaining more than the 75knots on 21 manifold pressure, more like 80-85 knots, so I arrived early at Morpeth, and similarly early at Alnwick. It took about 15 minutes to Alnwick. Quite a calm, non-turbulent flight.

Once at Alnwick, I travelled west for a bit over the golfball radar thingamajig, and then back to Alnwick. Then I took up the heading back to Morpeth, and mosied on back.

On the way back, I noticed that the Oil Pressure had gone into the red. Steve had gone through what to do in loads of scenarios before I left.

Steve :- If the clutch light comes on and stays on for 8 seconds or more, pull the clutch fuse out, and land immediately

He went through a similar spiel for every possible scenario you could think of.

Apart from this one, sod’s law !!!!

But, I was high up, circa 2500 feet, and I had the time to think it through logically. My thought process went something like this….

David thinking :- ok, it’s something to do with the engine, so if that stops, it won’t stop the rotor going because of the sprag clutch. ok, ok……erm……Pressure is high, too much oil, nah, there was only 4.7 litres in. What’s the oil temperature ? It’s fine ! Oh, that’s good, maybe it’s a faulty instrument

At this point, I gave it a good bang. And nothing happened. But then about 20 seconds later, it came out of the red, and into the yellow, top of the green.

And relax……….

To be fair, I didn’t relax, and was on high alert for an engine failure just in case. I kept a very beady eye on the Oil Pressure. It did go back in the red again, but because the oil temperature was fine, I wasn’t overly concerned.

Steve had told me to ensure I was at least 2000 feet over Eschott (another smaller airfield). I was keeping my eyes peeled, and saw a light a/c (Cessna) which was quite close, but we’d seen each other, or at least I’d seen him/her, so there never felt like there was any danger there. Hopefully, that will be on the video that I’ll put up tomorrow.

I reported back to Tower once at Morpeth and was asked to join left base, which I did. I was number 1 to land, reporting finals. Before I had chance to report finals, I was cleared to land, but asked to expedite the landing as someone was on 4 miles final (behind me).

So, I kept the speed on and it ended up being a fast approach, 80/85 knots. I’d forgot to cancel carb heat, not drastic with just me on board, thankfully.

I ended up doing quite a high flare, with very little collective pulled and a 15 feet high taxi (should be 2 to 5 feet) to get out of the way of the incoming. Steve suggested that i was quite within my rights to say “negative” to the request to expedite my landing. I am definitely too polite at times.

Now, this is where it got messy (in my book). I knew where to park, Steve had told me and the taxi and turn went fine, but then I started doing my “fart around for a minute” landings. I think the fast “transition to taxi” had made me tense. I could sense I was holding the cyclic very tightly, never a good sign and not something I generally do any more, but obviously, I did today.

Well, as can be seen by the video that I’ll put up, it wasn’t pretty to look at, but it was safe. I was up and down like something that’s up and down a lot !!

Eventually, I was down. For a second, I thought I’m going to do that landing again, so I can end on a good note, but then I remembered the oil pressure issue and thought better of it.

So, really enjoyable flight. Next flight, next friday. I’ve booked one for wednesday too, but there’s an appointment with kp on wednesday, so I’ll need to cancel that one.

Lesson 17 – 10th July 2009 – 1400 – 1 hour – Total so far – 19hours 33mins

Friday, July 10th, 2009

Today was Exercise 16 and 17. (Simulated Engine Off Landings and Advanced Autorotations).

CAA Inspection going on at the flying school today, so quite a busy place. It was the HP R22 today again as G-MOGY is due her 2200 hour overhaul and G-MAVI is having some engine work done.

We wheeled her over for fueling, and Steve let me do it. I’d remembered from last time to get the rotor in line, but as we pushed it, the wind caught the rotor and it started turning, so tip number 2 —-> Hold your shoulder in such a way the tail rotor doesn’t move, and if it doesn’t move, the main rotor can’t move.

Once fuelled up and pushed back, Steve left to check her out as I did all the checks, started her up etc…..

Runway 25 when we left, right turn to Morpeth after the car park. Magnetic compasses have a tendency to overread or underread depending on which direction you’re turning through, but I can never remember which direction they under or over read. Steve gave me a good way of remembering it…..

Nippy North, Sluggish South.

Nice one ! So, if you’re turning onto a northerly (or near northerly) heading, then stop the turn when it reads 330/340 and then the compass should settle to about North. It worked !

We went upto 2400′, and we’re tootling along quite happily. I was scanning the instruments and noticed we had ZERO oil pressure. I immediately told Steve and his response :-

Steve :- 20 Seconds

dp :- ? (puzzled look)

Steve :- It took you 20 seconds to notice that the oil pressure had dropped to 0.

He was pleased that I had noticed fairly promptly, so I was pleased. He’d pulled a fuse out.

I’ll have to watch him in the future. I suspect other such tricks up his sleeve.

Once we were close to the plateau, we did the Hasel checks (Height, Area, Security, Engine, Lookout), apply carb heat and we were doing Advanced Autorotations. So, a typical auto goes like this…..

  1. Lower Collective fully, Throttle engine down
  2. Lots of Right Pedal to counter lack of usual torque
  3. Cyclic Back so nose doesn’t drop too much and to maintain 60kts
  4. Control RPM (stop it getting into the red (too high or too low)
  5. Wait until the ground is 50′ feet away
  6. Flare (until Zero ground speed)

Now, then at this point, Steve always says “Pop” and I thought he was throttling up the engine again AND at the same time pulling the collective. So, when it came to my turn to do the whole maneuvre, the first bits went fine and we positioned for our forced landing, and then Steve had said I would be doing the final POP.

He constantly talked to tell me when to do it, and at the appropriate time, I flared, and opened up the Throttle and pulled the collective. It turns out, I wasn’t supposed to do any throttle work. The correlator sorts that out automatically. So apparently, (I was too busy to witness it), our revs went “quite” high !! And the subsequent hover was a bit erratic for about a second.

So, we did it again, and this time, I just did the collective, no throttle and I think there’s a 80% chance we would have lived, maybe 20% chance the helicopter would have been in good nick. I was too high and hadn’t flared strongly enough for the low wind speed that there was today.

The next one was better still. 95% chance of survival and 40% chance of a good helicopter remaining. No doubt, we’ll do plenty more.

What we then went on to do was advanced autorotations. In a nutshell, the standard auto detailed above has quite a shitty descent rate, probably moving 10 m forward for every 100m you’re dropping, so not much of a glide.

But, by altering the speed you fly, you can get more or less range.

Medium Range = Speed up to 75kts
Short Range = Speed to anything as low as ZERO knots, remembering to allow time to speed back up again as the speed will be required for the flare.

There’s also a maneuvre you can do to increase range even further. It sounded VERY risky to me, and that is to reduce rotor RPM to about 90%, giving more lift. Less than 90% and you’re in the danger zone and you risk the blades folding up, and then it’s death for sure, hence my worry. So, we did one of these, but all I was bothered about and focussed on was the rotor rpm. We were on or slightly above 90% and we’re getting a good gliding angle (by helicopter standards). I am sure as we flared, the low rotor rpm horn went off and that always puts the shits up me. But Steve wasn’t phased.

Anyway, we did various different advanced autorotations and then a fake landing and then we flew back. Runway 25, but the wind had changed and it was Runway 07 for landing. Another bit of non-standard flying which was fun back to the parking spot as there was a Dash a/c behind us on final approach, and then my landing today was MUCH improved over Wednesday when I made a right arse of it. I’d had a word with myself and didn’t fart on as much.

So, good lesson. Next lesson booked for Monday, and it’s more solo work. I’m flying to Morpeth and back on my lonesome after doing it once with Steve, so look forward to that.

I also managed to transfer Steve’s video footage that he kindly took with his phone camera of my first helicopter solo liftoff and landing. Here it is….

So, here’s the liftoff. Not very pretty at all !!! Major Yaw to the left on liftoff. But then the clearing turn is “ok”, could be worse, definately could be better.

It’s a bit grainy, but he got an excellent shot of me with the biggest smile I have ever seen on my face after I had landed for the final time on the first day of solo’ing. Here is that clip……

Thanks to Steve for getting the footage ! :-)