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Guest eland2705
Posted

I know it's not RA, but has anone heard anything about a RAAF a/c incident at RAAF East Sale this arvo.

 

Sounds like a PC-9?

 

 

Guest jabiru
Posted

Why not Land? when you are 1km short of the runway ?Sitting here in my office that is easy to say ! The boys are alive and that is what counts.

 

 

Posted

Standard operating proceedures, and Sqn orders prolly give them a mandatory eject and good airmanship dictates you throw the aircraft away in a direction that precludes collateral damage. If it was the same failure as the last then it would be very catastrophic with flames out the exhaust stubs, so it would have been zoom, trim, pcl off, adopt the position then exit straight up.

 

 

Posted

The pilots are worth more than the Aircraft. And as a tax payer i don't mind buying them a new one.

 

 

Posted

Yep that's why I do glide approaches, no ejector seat and no one will buy me another plane.

 

 

Guest ozzie
Posted

Bet the aircraft is laying in the middle of a flat cleared paddock. :(

 

 

Guest extralite
Posted

I thought the video said approx 1 mile on upwind, not approach. Turnback height usually briefed at no less than 600ft...usually higher. They are not cleared to land on unprepared surface with small wheels of high PSI and fuel in the leading edge tanks that rip easily. As said above, if it was upwind loss of power below approx 700ft then mandatory ejection.

 

 

Posted
I thought the video said approx 1 mile on upwind, not approach. Turnback height usually briefed at no less than 600ft...usually higher. They are not cleared to land on unprepared surface with small wheels of high PSI and fuel in the leading edge tanks that rip easily. As said above, if it was upwind loss of power below approx 700ft then mandatory ejection.

For some reason I thought it was an engine failure on final and not the initial leg, I agree losing power on take off can be a real problem. I had been under the impression that jet engines are particularly reliable.

 

 

Posted
I had been under the impression that jet engines are particularly reliable.

They are.

 

Until they aren't.

 

When the one that fails is yours, well, you lose faith in statistics and have to deal with it.

 

As the old hippie slogan says, "one nuclear bomb can ruin your entire day".

 

dodo

 

 

Guest turnbase
Posted

Just got some more information from a very reliable source.

 

The engine of the PC9 was lost some 10nm away from East Sale and while both pilot and instructor thought they could make it back to the field but couldn't and ejected very close to base. Would love to know the glide speed of these slippery blighters and it goes to show how good their skills were to get that close. They both ejected at around 300 feet which shows just how committed they were in returning to the field. One pilot is out of hospital with bruising while the other fared a little worse with a neck injury from the ejection. He is reportedly going to make a full recovery and be back to full duties in due cause albeit a little shorter. I've spoken to a number of pilots that have ejected and while the alternatives would have been a different story they are all still here to tell their story. All say how traumatic pulling the lever and smashing through the canopy. Only the Hornet still has a rocket powered canopy release most other aircraft rely on the seat or explosive charges to break the canopy.

 

I just hope both pilots aren't adversely affected by this ejection and continue on to be Australia's finest.

 

 

Guest extralite
Posted

In regards to glide approaches, it isnt actually that good, depending i suppose on what everyone is used to. For a ball park estimate to see whether it was a makable distance just double the height (after subtracting height to arrive at airfiled). So at 8000 feet, subtract 1500ft to arrive at low key abeam the airfield, so 13 miles glide range nil wind. There are a few variables in there, such as how it behaves with a feather prop rather than practice situation which is a power that is estimated to simulate a feather prop, wind etc. Although an advanced student should make an ejection decision at 1500ft at low key, instructor would go for a straight in glide approach and so could stretch it much more.

 

So typically, doing air work at say 8000 feet, glide range may have been up to 20 miles for an experienced instructor...or at least worth a shot rather than head to the pre planned ejection field. Also get a bit of a ballon effect as take off flap is selected late finals which is what might have been hoped for, but wasnt enough which could exlplain a low ejection decision. If it was a long glide it would be unusual to make an ejection decision so low (decision to continue made at 1500ft low key) but who knows what went on at that time.

 

The PT6 engine (turboprop not jet) is generally very reliable. The PC9's do a lot of hours with a lot of throttle bashing, aerobatics and circuits which is not what the original engine was designed for. Last I heard there had been very few engine failures that were not attibutable to the electronic fuel control unit which is overidable with a manual system anyway. So interesting scenario and testament to the ejection seat (and the maintainers of them) that they survived in a low altitude and probably not much upward trajectory situation. Great both guys survived.

 

 

Posted
Any info on why they were unable to land? Or did I miss that?

From previous posts it seems they could not make the strip due to lack of height, ejecting at 300 ft must have been tight. Those type of aircraft would not be suitable for out landings. I thought a turbo prop turbine was still a jet engine.

 

 

Guest extralite
Posted

Usually Turbofan or Turbojets are descibed as "jet" engines rather than Turboprops...but its a technicality I guess. Turboprobs also use a gas turbine, but use a propellor for the majority of the thrust rather than the exhaust.

 

 

Guest ozzie
Posted

Gas turbine is the correct term. Fuel and compressed air is fed into a can where it is ignited and expands rapidly, this gas is forced downstream and turns a turbine wheel that drives a compressor to pump air into the can this wheel willl also drive other items like fuel/oil pumps etc. The gas will then flow through another independant turbine wheel that will drive the propellor reduction gear box and turns the prop. Once lit they are self sustaining and you can remove the ignition source. They still work on the suck squeeze bang blow principle but do it all at the same time. around 90% of the power produced goes back into driving the compressor. The PT6 like the one fitted to the PC9 and the RR/Alison fitted to the Nomad and Jetranger are 'freewheeling" turbines You can hold the prop and start the engine and it won't move. The Garrett Turbine is a fixed turbine and the power turbine is directly coupled to the prop box. And idle at around 92% from memory.

 

Trivia, An Alison B17B (nomad) has a 5 stage axial and 2 stage centrifugal compressor and can digest 42 cubic feet of air per second at full cry. That's thru a 5 inch dia inlet.

 

They are reliable as long as dodos don't play with them.

 

 

Posted

My cousin flies the PC9, glad these guys got off well, would certainly have been a hair raising situation.

 

 

Guest turnbase
Posted

To add to the information I believe the engine failure was at around 3000 feet which adds even more complexity to how much workload was happening in the cockpit. What amazes me was that they almost made it.

 

Further it is standard practice to preserve both pilots than machine. Engine is being stripped as we speak to identify problem but if the last engine out and fire a couple of months back was a consideration then it will

 

probably end up being only a coincidence. The last engine fire I believe was put down to an isolated manufacturing part failure. With thousands of the PW turbines in service only a few have had problems.

 

Hope this is just one of those things and not a repeat performance.

 

 

Posted

I was just looking at the pictures a bit more... I think it's pretty cool how well the aeroplane landed it-self - sure it's rather smashed up, but considering it was pilotless it looks reasonably recognizable.

 

 

  • 2 weeks later...
Guest turnbase
Posted

Just got the word that hopefully this week the PC-9 fleet will be back in the air. The problem was reported to be some sort of fuel pump failure. Very little info apart from that at this time.

 

 

Guest ozzie
Posted

Small snippet in today's newspaper, fuel control unit failure and they are consulting with the maintenance contractor. I think the other loss was also fcu. Hmm wonder if it's the same type on our Cresco

 

 

Guest turnbase
Posted

Ozzie, from my knowledge the first failure was from a totally unrelated part failure that was traced back to the manufacturer. This was an isolated incident as PW have confirmed that the part failed.

 

 

Posted

Turn base your right the first failure was on the runway at RAAF Pearce, solo female student advanced the PCL to max for takeoff, at 40 knots the turbine tried to come through the exhaust stubs.

 

 

Guest turnbase
Posted

Thanks deadstick the only information that I heard was that one of the very small fan blades had a minor flaw that wasn't picked up during quality. While this is a safety issue you can also understand the amount of blades that are manufactured and never miss a beat throughout their working life. I believe that the part while having undergone x-ray was still approved. Just goes to show while the manufacturer took every step to provide safety things still happen.

 

 

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