dutchroll

Yes we strongly suspect that's what happened. It wouldn't have been a backfire I don't think, rather an afterfire. Fortunately! Yep. Still not scratched!

Early during the circuit I would've had the ability to land on the cross strip, albeit with a fair crosswind. Would've needed some fancy manoeuvring, but achievable I think. Later in the circuit, because I deliberately kept it very tight, I could've turned an early base and touched down halfway down the runway, or just landed across both runways using the grass.

Had a partial engine failure today departing in the Pitts which involved repeated huge "backfiring", accompanied by belches of black smoke (according to witnesses) and temporary substantial loss of power (followed by recovery each time) from about 100ft after takeoff. I immediately turned onto the tightest downwind I've ever flown, pulled the power back a bit (which somewhat reduced the severity) did some quick trouble checks (boost pump on - already was, mixture, fuel on main, ignition switches, phew, at least I didn't skip my checklist actions before takeoff!) and had obviously caught the attention of tower who quickly asked "confirm Ops normal?" - answer "negative, rough running, returning for immediate landing". They immediately cleared me to land on any runway (good job ATC). With much reduced power on a very tight base and final the backfiring stopped and the landing was uneventful, though with the significant noise I had quite an audience out the front of the hangars. The whole incident was probably 4 minutes. So.....what was the problem and why do I feel like stabbing myself in the eyeball with a fork? After a day attending to air system issues and the maintenance guys doing several engine runs I was heading home. I had abnormally low egt indications on #5 cylinder during the runup. It sounded good though, the other 8 cylinders were fine, and the mag drop was insignificant. I quickly sms'd the maintenance guys who were not far away from the runup bay and they replied that it sounded really good from outside. Bad probe? CHT was low on that cylinder but rising and coming within limits (warning sign ignored perhaps also influenced by get home-itis). So I made the fateful decision to takeoff. Application of takeoff power was normal but we figure (will find out on Monday) that both plugs were totally fouled. The EGT indication was correct. The CHT was rising with heat produced by the perfectly functioning neighbouring cylinders. The mag check was normal because neither plug was operating, so switching each ignition off in turn made no difference. Giving this 436HP beast full power poured a gutful of fuel into the #5 cylinder which was fine for a very short time, but probably ignited the exhausted fuel mixture with a bang in the hot exhaust pipe very soon after takeoff. This probably produced substantial back-pressure, causing the instant power loss then recovery, until the next lot ignited in the exhaust with the same result. Reducing power reduced the fuel flow and consequent effect. Ironically, if I didn't have an engine monitor (and many aircraft powered by these engines don't), the result would've been the same. However I did have one and it gave me 2 warning signs which I noted, but dismissed (abnormal EGT and slow rise in CHT in the same cylinder, in favour of the fact that it "sounded good" (and it truly did) and was a normal runup, with nothing out of limits. Something I need to have a long hard think about when I finally stop hitting myself. I really need to pay more attention to the generous indications I have on the engine monitor rather than only being concerned with a flashing out of limits condition. EGT doesn't have this, but can tell me a lot.

I'm simply making the point Nev that "it's only a hobby, therefore I shouldn't need to keep compliance documentation" is not a very good argument and it doesn't wash anywhere in the world, except in despotic 3rd world countries with little or no functioning legal system. I could've used any of dozens other examples of "private hobbies" where licensing, compliance, possible inspection of paperwork, etc are all applicable. Honestly, if people truly want to be completely free of the "burdens" associated with doing stuff in a society, they should go and live in a remote cave in the mountains somewhere, but as soon as you start interacting with others, you have to deal with documentation/compliance/inspection regimes, and where you have those, you could have a requirement to produce evidence of it at any time. Building something on your own block? You can be required to produce evidence of building compliance - even years later. Going rabbit shooting with the lads? You could be asked to produce a licence, and you could be randomly inspected at home for firearm security. Driving to a picnic? Firstly in most States you can't even renew your annual rego without inspection paperwork being forwarded to the appropriate authorities. You could also, if you are stopped, have your family Commodore inspected for defects even if there's no obvious reason there should be any, and asked for licensing documentation, and have your registration checked. What is it about flying a plane which makes some people feel they should have special privileges and be exempted from this stuff?

Flying a Cessna 172 with your family on the weekend is a hobby/recreational. Is it your contention that Cessna 172 maintenance records are an unnecessary burden?

Auditing to ensure compliance or that standards are being met is a fact of life in most occupations around the world. I'm mystified as to why anyone would have any issue with it on principle. As has been pointed out, if you can't prove from your paperwork that the correct standards were met, expect your insurance company to drop you like a hot potato. If you end up in court, you may end up losing much more than you think (like your house, etc). Never mind what the Government says, it's what the private organisations like insurance companies and law firms will do which is going to screw you over when you don't have the proper compliance documentation.

Sorry...making assumptions again from my experience in forums like VAF where the experimental crowd all seem to know what it is - probably because they're spoiled with Nextrad, the Universal Access Transceiver on 978MHz, etc which give them traffic displays at the drop of a hat, and which we don't have here in Australia.

Sorry.....my bad. ILS Precision Runway Monitor. Applicable to closely spaced parallel runway systems - e.g. Sydney. The use of precision radar equipment (which is what the article is about) allows the aircraft on these parallel runways to be more tightly packed together. Normally due to the proximity of these parallel runways there is a minimum 2nm stagger between approaching aircraft on the left and the right conducting ILS approaches. With the PRM equipment, there is no minimum stagger. They can be right next to each other. There are special ATC and pilot procedures which apply if an aircraft diverges from the localiser course which will result in both aircraft executing a "breakout" (fancy name for a go-round under ATC instructions, turning away from each other). Taking away all the technobabble, the net result is that with this equipment Sydney airport can handle more movements per hour in poor weather conditions. It seems that this equipment is having reliability problems, which means the movement rate would slow down as the 2nm separation would need to be reapplied when it's broken. As far as "safety" concerns go, I'm personally not really too fussed if the equipment works or not. Though it would be a pain for ATC at the last minute to suddenly have to apply the increased separation, and it would cost airlines money as they deal with consequent ATC delays. If the equipment fails while two aircraft are actually on approach next to each other, that doesn't mean they're suddenly going to crash together. They're on autopilot locked to the localiser beam and course deviations under those conditions are exceedingly rare (never seen one in my career personally). It would be more of a problem if two aircraft were head-to-head on opposing vectors about to intercept their respective ILS's simultaneously, and one of them didn't capture it properly and went through it. That's uncommon, but I've seen it happen and it can be due to the pilot not pushing the right button to arm the capture mode and the other pilot not picking up the error, or it can be due to the aircraft nav system not picking up the beam when it should and capturing it late, which is the case I've seen. Of course in this case you also have TCAS helping you (we all know what TCAS is I'm sure!).

Hmmm..... So this radar system is critical to ILS PRM approaches. I could count on one hand the number of ILS PRM approaches I've done in Sydney in the last 12 months. However I'd need lots of hands to count the number of ordinary ILS approaches I've done. I personally haven't noticed any significant changes to delays, holding times, etc.

I think we've put the argument to bed (as much as that's ever possible among a group of pilots) on the other forum, but interestingly it has emerged that there is a loosely scattered group of junior controllers who are insisting on a "when ready" readback from pilots, but there is also a group of senior controllers trying to correct them and informing them it's not necessary. The reasoning apparently given by one of the errant juniors was "well I need to confirm that he understands he's not required to descend straight away". I think that's poor reasoning from the junior guy. It's really the pilot's problem if he starts his descent early when he doesn't need to. It's not a safety issue as the descent clearance is valid either way. He'll just need to shallow out his descent profile, and there'll probably be a guy next to him muttering "See? I told you it was when ready!"

Well this is the problem and I'm the last person to suggest that CASA's regs are always well thought out. I have no objection to drone operators per se. Just the idiot ones. We need to stomp on the idiot ones out there because they are proliferating and the responsible ones will find themselves in a minority eventually!

Intrepid ATCers...... Debate raging on company forum (in a humorous way, but it's on page 4 now and has suffered thread drift with lineup and takeoff clearances): "(Callsign) when ready, descend to ........." Is it necessary to read back "when ready"? I would suggest no it is not and I never do, nor do many I fly with. One or two are trying to say that this is a conditional clearance, but I'd disagree. There is no condition attached. Controller is just saying in effect "descend whenever you like - I don't care at the moment". Thus the normal requirement to initiate descent within one minute of receiving the descent clearance does not apply. The question originated because one of the guys recently had a controller insist he read that bit back. First time I've ever heard of that happening.

No, it was alleged by the Britsh Transport Minister that the drone strike "may have even been a plastic bag or something" (his exact quoted words) followed by "we're not quite sure what they saw" (again his exact quoted words). I don't know how you leap from those two statements from a serving government politician to "it turned out to be a plastic bag". FYI there was a drone near-miss in Adelaide at 1,100 ft a couple of weeks ago. Here's an example of what we're dealing with, from a drone operators forum (this incident occurred late last year):

Oh well if that's what the British Transport Minister said, I guess we can take that as absolute gospel then! Here's another quote from him in the same article: Well there you have it! The British Transport Minister hasn't actually landed a B747, but heck he's landed the simulator once, and thus we can reasonably conclude he has all the necessary expertise to know exactly what pilots on final approach to one of the busiest airports in the world are doing and seeing (because the 20 other aircraft on frequency and the extremely busy Air Traffic Controllers are so accurately replicated by the simulator instructor talking the Minister through a landing). But wait....there's more from the Minister: The [/url]Telegraph reports that Goodwill could not confirm the identity of the object that struck the British Airways Airbus A320 as it prepared to land last Sunday. Synopsis: "The Minister says it could've been a plastic bag, but he can't confirm it, but who knows what the pilots saw, because he landed the simulator once, so he knows what it's like." Uh huh.......

I meant to say on earlier here that it's not 100% (maybe 99%) a careless switch selection or wiring fault which can cause the thing to fire. It is possible for a hot engine to "diesel" if you swing a prop with enough compression and a bit of fuel vapour left in the cylinders, even without a live mag. I know someone who has had it happen.

Still done that way on Airbus models (full control check with synoptic page showing control surface deflection) just before taxy. Don't call anything related to flight controls at 100 kts though. Our company had an uncommanded autopilot engagement just after takeoff on a B767 some years back. I know the guy who was flying it pretty well. Flying pilot thought he'd lost control of the plane because the controls froze, but the other pilot instinctively pressed the autopilot disconnect and they got the disconnect warning much to their shock! To this day I don't think they know why it self-engaged, as it's quite a distinct button press on the glareshield to engage the autopilot.

They were doing an engines running offload/onload and the USAF checklist for that doesn't call for a flight control check. Somewhat unbelievably. So there were several holes, as usual, lining up in this accident sequence.

I'd go the whole hog with a transponder, even though you can still buy the cheaper Mode C only variants. The problem is this: you never quite know when the regs will become more restrictive (as they're tending to do with transponders and ADSB), and also you never quite know where you'll be inclined to take your little plane in the future as far as controlled airspace goes. If you get a Mode S, "ADSB capable" transponder (this doesn't mean you actually have to buy the GPS equipment - just that you can add it later if you want) you are fairly bullet proof for the future.

I never said the RAAF did things the easy way! But by the time you'd repeated it dozens of times it just flowed off the tongue.

No-one is impartial. So it's pretty rich hearing a rec pilot tell a professional pilot he's not impartial! May I suggest taking a quick glance in the mirror? I'm not impartial about safety of flight issues when carrying 300 passengers, and I will not apologise for it here on this forum. Although still numerically small, the increasing trend of reports of near misses with drones at certain major airports is an empirical fact and aviation authorities are becoming concerned. Wishing it was all some big commercial pilot fantasy is not going to make it go away. There are many things we fantasise about. Getting up close and personal with a drone on takeoff and final approach is not one of them. If I was certain that I saw something nearly collide with my Airbus A330 and which was obviously controlled by a human, I would be making sure people know about it too. Just like when I got lasered straight in the eyes on final approach in a Boeing 767 to Sydney Airport one night. I whipped up a bit of a stink about that too. Should I just get over it and accept that incidents which affect safety of flight happen and just forget about them? I mean relative to the number of flights, there are very few of these incidents. Are we commercial guys being overly precious about it? Should we just go home and forget about it? Leave the poor drone operators (and idiots playing with lasers) alone?

You're equating myself and my airline pilot colleagues to aircraft salesmen and telling me that if I don't spruik garbage, I'm the exception to the rule? I'd like you to know that I and all my colleagues take air safety incident reporting very seriously. If you have evidence to the contrary, let's have it out here. ........and because this is your opinion and you don't like some people's political views on this forum (or your perception of them at least), it means airline pilots around the world would just make stuff up - fabricate a report - about a drone near miss or collision? Are you listening to yourself? Source: UK Air Proximity Board, the outfit which monitors reports of near misses.... 17 April 2016 - A British Airways plane approaching Heathrow is believed to have hit a drone while in midair 28 November 2015 - The pilot of an A321 plane narrowly missed a drone hovering at 100ft above a runway at Gatwick Airport 30 September 2015 - A small drone helicopter passed within 30ft of the cockpit of an A319 plane while on the approach to Heathrow 22 September 2015 - A "quadcopter-type drone" missed the right-hand side of a B777 plane by about 25m while at 2,000ft after it left Heathrow Airport 13 September 2015 - A silver drone with a "balloon-like" centre missed an E170 aircraft by about 20m, while the plane was approaching London City Airport over the Thames 13 September 2015 - A drone flew over the top of a B737 aircraft while at 4,000ft, missing it by about 5m, shortly after it left Stansted 27 August 2015 - A DO328 aircraft flew within 50ft of a drone while approaching Manchester Airport at 2,800ft

Well.....I'd argue that an airline pilot would be an idiot to make up a story about nearly being hit by a drone when no such incident happened. I really would. I'd suggest that it doesn't go on "all the time" unless it's part of your job to tell tall stories, and it certainly doesn't go on all the time with professional aviators. If they said it was a drone which hit them, then it was most probably a drone which hit them. If it was actually a sparrow or something, then so be it. I think it's likely they could tell the difference. In the case of near misses, if they couldn't clearly recall what it was, they would probably think it was a bird and not report it, as often happens.

I have on numerous occasions clearly identified a bird in near misses on takeoff and final approach, in a large passenger jet, from the cockpit. In most cases both of us positively identify it, right down to approximate size, the flapping wings, the head, the colour, which direction it was heading, etc. You might be surprised what a clear view or snapshot you can get, even at takeoff and final approach speeds. Airline pilots, with a few exceptions, are generally not blithering idiots who go around making stuff up.

Not really. We try to protect the rest of the population from their idiocy. This even strikes to the heart of such topics as safety helmets and so on. If they smash their own head in through stupidity, so what? But there's a bigger picture out there involving the rest of us paying for emergency services, paramedics, hospitals, insurance premiums, and all manner of other stuff which costs us dearly because of their stupidity. As I said......this is why we can't have nice things. Drones in 4 near misses at major UK airports: https://www.theguardian.com/technology/2016/jan/29/drones-near-misses-major-uk-airports-heathrow-stansted

I guess it reinforces that the pilot's flight control check before takeoff is the absolute last line of defence. During our basic pilot training it was so drilled into us....... "stick left, left aileron up, right aileron down........stick right, right aileron up, left aileron down.......stick back, elevators up.....stick forward, elevators down........rudder left, rudder right......full and free movement". If you didn't do that it was an instant "fail" grade for the whole flight, and reprogramming for a "repeat". That was in addition to the tense debrief, and the punishment of running the length of the airfield to the runway "sight board" near the threshold and back, with your parachute on. So nobody ever forgot a flight control check, to my knowledge!