Well after 800 hours of TW time I finally bolloxed it up
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Aye, and looking down the Vale of Strathmore at this very moment from my office with a view, the spare won't be going anywhere as PB's home pad is being battered by dust storms. They're not visible all the time.....just when the blizzards stop for a wee while.
Commiserations PB.
Commiserations PB.
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Sorry to hear of your misfortune piperboy. These @rsedraggy things always scared me. A bit like a dog with piles. BTW have you ever watched the rudder on rollout? 
As NorthernChappie says don't rush home. 350/30G40 rain,hail, snow and probably ****e coming out of the sky as well in Forfar.
As NorthernChappie says don't rush home. 350/30G40 rain,hail, snow and probably ****e coming out of the sky as well in Forfar.
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Aye, and looking down the Vale of Strathmore at this very moment from my office with a view, the spare won't be going anywhere as PB's home pad is being battered by dust storms. They're not visible all the time.....just when the blizzards stop for a wee while.
Commiserations PB.
Commiserations PB.
Shrewd buggers those Aberdonians !!
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BTW have you ever watched the rudder on rollout? 
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Ah! I did wonder if it was a reference to the frantic rudder waggling one sometimes sees when a taildragger lands. Well, it shouldn't happen, though one or two large rudder inputs towards the end of the roll out are not unusual.
If the rudder is wanging left and right throughout the roll out like salmon's tail as it leaps over a weir on its way up-river, then that is PIO - over controlling. The pilot is sensing a yaw, over-correcting, then over-correcting the over correction. An experienced taildragger pilot will not do that; rudder inputs will be few and small, with, as I say,perhaps a couple large deflections right at the end of the roll-out when rudder authority has become poor.
If the rudder is wanging left and right throughout the roll out like salmon's tail as it leaps over a weir on its way up-river, then that is PIO - over controlling. The pilot is sensing a yaw, over-correcting, then over-correcting the over correction. An experienced taildragger pilot will not do that; rudder inputs will be few and small, with, as I say,perhaps a couple large deflections right at the end of the roll-out when rudder authority has become poor.
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We may be drifting PB's thread here, but he's gracious, so perhaps will indulge us a little...
Yes and no.. The excess or non required movement of a flight control, which results in no or little change in the aircraft path does do two things: It wears the flight control mechanism a minuscule amount, which I think we can tolerate, and, it creates drag. Otherwise as SSD correctly observes, it looks a bit fishy from the sidelines, but is otherwise harmless.
The only "training" I ever had in taildraggers which I felt was meaningful was in a 185, in which my mentor correctly observed that I was freezing on the controls (out of fear - I was!). He instructed me that as the first wheel touched, I was to rhythmically move the pedals so that my feet were not frozen, and application of the required control became a bit more or less of a motion which was happening anyway, rather than not happening, because I had frozen. I found this worked.
I do this less now, as I have seemed to have learned to fly taildragger, but I still apply meaningful, and possibly excessive rudder input during a rollout, as my runway is very narrow (4 feet off the centerline, and I'll be taking out runway lights with a wingtip float). I also find that on uneven surface runways, as the bumps are absorbed left or right, the plane may roll then yaw a little with this motion, and rudder input is required to counteract that. I'm not embarrassed to be seen to wave my rudder like a fish, if it makes my landing very well controlled.
As for a yaw PIO - yes, it can be done. However, by the time it gets to that, there will either be a lot of squealing tires or mud and grass flying around. PIO will indeed be caused by gross overcontrol, but more matter of being too late then too much with the pedals. The pilot sensing yaw, and reacting crisply and moderately to prevent a yaw excursion is less likely to PIO in yaw, as the pilot reactions will be at a rate much faster than the inertia of most planes to swing in yaw.
Excess control movement creates drag, which occasionally is a good thing. Like during landings. That said, I do not suggest waggling the flight controls, on an airplane to slow down - really poor airmanship! However, there is une instance where it is done, and that is in some "stuck pedals" situations in a helicopter, when you would like to descend in a hover without reducing power. You can slop the cyclic control all over, and create drag, and the helicopter will settle with power, without yawing (much). That does work, for the very few times you might ever need to use it in your helicopter.
If the rudder is wanging left and right throughout the roll out like salmon's tail as it leaps over a weir on its way up-river, then that is PIO - over controlling.
The only "training" I ever had in taildraggers which I felt was meaningful was in a 185, in which my mentor correctly observed that I was freezing on the controls (out of fear - I was!). He instructed me that as the first wheel touched, I was to rhythmically move the pedals so that my feet were not frozen, and application of the required control became a bit more or less of a motion which was happening anyway, rather than not happening, because I had frozen. I found this worked.
I do this less now, as I have seemed to have learned to fly taildragger, but I still apply meaningful, and possibly excessive rudder input during a rollout, as my runway is very narrow (4 feet off the centerline, and I'll be taking out runway lights with a wingtip float). I also find that on uneven surface runways, as the bumps are absorbed left or right, the plane may roll then yaw a little with this motion, and rudder input is required to counteract that. I'm not embarrassed to be seen to wave my rudder like a fish, if it makes my landing very well controlled.
As for a yaw PIO - yes, it can be done. However, by the time it gets to that, there will either be a lot of squealing tires or mud and grass flying around. PIO will indeed be caused by gross overcontrol, but more matter of being too late then too much with the pedals. The pilot sensing yaw, and reacting crisply and moderately to prevent a yaw excursion is less likely to PIO in yaw, as the pilot reactions will be at a rate much faster than the inertia of most planes to swing in yaw.
Excess control movement creates drag, which occasionally is a good thing. Like during landings. That said, I do not suggest waggling the flight controls, on an airplane to slow down - really poor airmanship! However, there is une instance where it is done, and that is in some "stuck pedals" situations in a helicopter, when you would like to descend in a hover without reducing power. You can slop the cyclic control all over, and create drag, and the helicopter will settle with power, without yawing (much). That does work, for the very few times you might ever need to use it in your helicopter.
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27/09
My father was an AT-6 (Texan/Harvard) instructor in WWII. Once he was called upon t retrieve a ship that a student was ferrying - it ran out of gas and daylight about the same time, and landed gear-up in the desert. Bent prop, a few minor dents. They sent a truck w/ crane and techs with tools to put it back on its gear and check the crankshaft, which they did with a dial indicator. Dad was a toolmaker in civilian life so he was familiar with the task. Crank checked OK, they topped off the tanks, hung a new prop, and he ferried the AT-6 back home.
I don't know the exact parameters but you may get away with a runout check on the crankshaft prop flange and, if that's within limits, just a new prop.
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Talked to an engine shop and insurance today, they are obligated to do a full tear down and inspection which is fine by me, the engine shop mentioned I may want to look at "port cleaning" while its apart. Scouring the internet I read where this can give you an extra 5hp per cylinder !! It sounds good but is this just more aviation " tastes great/ less filling" BS?
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I dont know about your engine but in most cases the ports have a rough finish from the casting process. Motorbike racers go to great effort with special grinding tools to get around any bends and polish the ports to a mirror finish which reduces turbulent flow.
So maybe a good idea to release a few extra horses.
OTOH the gas velocities in a slow turning aero engine will be a lot less than a highly tuned bike engine so maybe......
So maybe a good idea to release a few extra horses.
OTOH the gas velocities in a slow turning aero engine will be a lot less than a highly tuned bike engine so maybe......
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A dial indicator is an instrument originally mechanical like a pocket watch, though now more digital, which has a probe projecting from the base. The probe will touch a surface and with rack and pinion gears, cause the pointers on the indicator to indicate distance, often down to .001". So you can clamp the indicator to the engine case with the probe on the crankshaft flange, and turn it. If the crankshaft has been bent, the indicator pointer will indicate a dimension change as it is turned, and you know it is bent. If no "motion" of the indicator pointer is seen, no bend in flange (though a cracked crankshaft is still possible). Lycoming cranks are reputed for being undamaged following a prop strike, when the crank flange "dials okay". PB you will have a quiet smile when you get the report from the engine shop, but the reassurance of the teardown is worth it. This also affords the opportunity for a good cam and lifter inspection, vital for Lycomings. Consider that if any defect is found in the cam or lifters, you would like to pay for new ones while the engine is apart.
If you have a prop which vibrates or won't track, this is a useful check, as the prop may be fine, and the crank flange out. (Though that might be a problem you'd wish you'd not found!)
"Porting" an engine, as described, involves progressively polishing the cast passages in the induction system, in the case of a Lycoming, the cylinder intake ports. This will improve induction airflow. It is considered rather labour intensive though, as it is usually associated with dynomometer tests to measure the effect and outcome. This can mean some re 'n re of the induction parts = cost. The idea is to improve airflow and balance the airflow between each cylinder, so they are equal. If after having it done, you have to change a cylinder, it'll have to be done to the new cylinder to match. There are flow measuring devices which are used to get close, so the airflow characteristics of each cylinder are close to that desired before first installation to the engine. I have been told that making the cylinder induction passage too smooth can have an undesired effect though, as the rough cast surface of the induction ports promotes turbulent airflow (like vortex generators), and keeps the fuel air nicely mixed. The engine shop I worked for offered this, but it was rarely sought.
If you have a prop which vibrates or won't track, this is a useful check, as the prop may be fine, and the crank flange out. (Though that might be a problem you'd wish you'd not found!)
"Porting" an engine, as described, involves progressively polishing the cast passages in the induction system, in the case of a Lycoming, the cylinder intake ports. This will improve induction airflow. It is considered rather labour intensive though, as it is usually associated with dynomometer tests to measure the effect and outcome. This can mean some re 'n re of the induction parts = cost. The idea is to improve airflow and balance the airflow between each cylinder, so they are equal. If after having it done, you have to change a cylinder, it'll have to be done to the new cylinder to match. There are flow measuring devices which are used to get close, so the airflow characteristics of each cylinder are close to that desired before first installation to the engine. I have been told that making the cylinder induction passage too smooth can have an undesired effect though, as the rough cast surface of the induction ports promotes turbulent airflow (like vortex generators), and keeps the fuel air nicely mixed. The engine shop I worked for offered this, but it was rarely sought.
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The excess or non required movement of a flight control, which results in no or little change in the aircraft path does do two things: It wears the flight control mechanism a minuscule amount, which I think we can tolerate, and, it creates drag. Otherwise as SSD correctly observes, it looks a bit fishy from the sidelines, but is otherwise harmless.
The same effect can be noted sometimes in elevator / aileron stirring on approach by some pilots, the 'stirring' being quite marked and far too rapid for the aeroplane to fully follow the control inputs before they are countermanded by the subsequent control input. I've been with some pilots who I'd say 'are a good pair of hands' and land just fine, despite doing this! I prefer to see few, definite, accurate, and smooth control inputs from a pilot to all flight controls than 'porridge stirring', even if the 'porridge stirrer' still controls the aeroplane OK!
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! I prefer to see few, definite, accurate, and smooth control inputs from a pilot to all flight controls than 'porridge stirring', even if the 'porridge stirrer' still controls the aeroplane OK!
Wiggle wiggle wiggle wiggle.......
PS Sorry to hear of your incident Piperboy....guess with the type of flying you do on a regular basis its rather inevitable you might have a minor prang at some point!
