Hypothetical Question from my Instructor. HELP!
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For such a question there is two answers.
1. If you fly at 2000 feet to ybdg from Melbourne there is a bloody big mountain called mount macedon in the road and terrain won't let you.
2. There is no direction that will make it feel faster. The clouds will move with the wind. I.e. if you track north your ground speed will be low however TRUE airspeed remains the same. If you track south, well good luck getting to Bendigo from Melbourne.
Stupid question requires stupid answer. But what he wants is for you to understand tas.
1. If you fly at 2000 feet to ybdg from Melbourne there is a bloody big mountain called mount macedon in the road and terrain won't let you.
2. There is no direction that will make it feel faster. The clouds will move with the wind. I.e. if you track north your ground speed will be low however TRUE airspeed remains the same. If you track south, well good luck getting to Bendigo from Melbourne.
Stupid question requires stupid answer. But what he wants is for you to understand tas.
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There are more intelligent questions your instructor can ask you rather than that sort of hypothetical stuff. How about you ask him the following questions which are more directly applicable to your 30 flying hours than which way clouds seem to go.
Please Mate (or Sir if you wish to be polite)
How do I know if the engine on my aircraft is delivering its certified power on take off? What is Minimum Static RPM for the aircraft I fly and where would I find that information. Ask him to show you - don't just take his word for it.
Secondly, Dude (Sir), what is it's relevance to my take off procedure and specifically how do I check it? And what are my actions if the actual RPM is above or below the published range of Minimum static RPM?
Your instructor should be able to tell you the correct answers to those questions since they relate directly to flight safety - YOUR flight safety
Please Mate (or Sir if you wish to be polite)
How do I know if the engine on my aircraft is delivering its certified power on take off? What is Minimum Static RPM for the aircraft I fly and where would I find that information. Ask him to show you - don't just take his word for it.
Secondly, Dude (Sir), what is it's relevance to my take off procedure and specifically how do I check it? And what are my actions if the actual RPM is above or below the published range of Minimum static RPM?
Your instructor should be able to tell you the correct answers to those questions since they relate directly to flight safety - YOUR flight safety
Last edited by A37575; 19th Sep 2012 at 06:11.
Elfatso, your instructor is just getting you to think relative to your aeroplane. Unless you come under the effect of windshear or downdrafts or thermals all the air around you is moving relatively with you as if you are flying in still air. If you are like a particle of air if you are sitting in a gondola of a ballon. Even though you are moving over the ground you perceive you are in calm no wind conditions. You are part of the moving parcel of air. If you observe an Aeroplane flying around you his airspeed relative to you will always be the same. As if the Aeroplane is also flying calm no wind conditions.
What will get inside your head later on is what happens to your performance due to inertia as you change direction in an airstream like turning from a headwind to a tailwind. Very important if you are flying a very light aeroplane.
What will get inside your head later on is what happens to your performance due to inertia as you change direction in an airstream like turning from a headwind to a tailwind. Very important if you are flying a very light aeroplane.
What will get inside your head later on is what happens to your performance due to inertia as you change direction in an airstream like turning from a headwind to a tailwind. Very important if you are flying a very light aeroplane.
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Guys I didn't post this thread so that everyone could have a dig at my instructor, I assure you I am learning as per the syllabus & he is a fantastic instructor, especially compared to some of the horror stories I've read on here with other instructors!
I love a good challenge to so I'm more than happy with these "hypothetical" questions.
Again I'd like to thank everyone for their time and assistance, I could have been quite easily ignored! (which is what I was expecting tbh)
Anyways, whats this "Downwind Turn Debate".... Or should I go thread searching?? Sounds interesting
I love a good challenge to so I'm more than happy with these "hypothetical" questions.
Again I'd like to thank everyone for their time and assistance, I could have been quite easily ignored! (which is what I was expecting tbh)
Anyways, whats this "Downwind Turn Debate".... Or should I go thread searching?? Sounds interesting
I think the general consensus here is that it's a fruitless question & serves no purpose to learning to fly.Don't forget yr instructor is just that, he's there to instruct.No one is born with any knowledge at all in any field we all learn along the way so get this rocket scientist to learn you & explain his theory & what benefit it would have on yr flying lessons.
At the end of the day flying just above the clouds is just a visual experience ( & a bit of fun)& you wouldn't be able to tell the difference anyway regardless of which way you where driving the plane (it would appear fast anyway) as you have nothing to gauge or compare against at the time.
Enjoy the flying, leave the rocket science stuff to the wannabees!
Wmk2
At the end of the day flying just above the clouds is just a visual experience ( & a bit of fun)& you wouldn't be able to tell the difference anyway regardless of which way you where driving the plane (it would appear fast anyway) as you have nothing to gauge or compare against at the time.
Enjoy the flying, leave the rocket science stuff to the wannabees!
Wmk2
Wally, actually, it is a very good question for those that don't understand or don't know how aeroplanes interact with the airmass they are in, and said movement relative to the ground. Not only for the rocket scientists but also for those curious about their flying machine, as it seems Elfatness is.
The dreaded downwind turn argument is a long term argument that upsets a lot of people for exactly the same reason as your original argument.
Without hijacking your thread. Heavy drivers understand what to do if encountering microburst conditions on approach to land. Heavies have(edit) lots of inertia. As the shear hits IAS changes...why is it so? Flying into the rapidly increasing airflow IAS increases...but the argument for relative airmass says there should be no change. ASI increases and aircraft starts to overshoot...pilot reduces power and lowers nose to regain approach path and then flies into the downburst, powers up and trys to arrest the sudden undershoot...so now the aircraft is nose up and under power trying to regain approach path and then aircraft flies into the strong tailwind of the microburst nose high and under full power and low energy...plenty of people have died until authorities finally believed the met guys that their aircraft can be brought down by an airmass. Me no heavy driver but it took a looong time before the authorities learnt to teach their drivers to go full power, nose up fifteen degrees and go round. More learned heavy drivers can give better description what SOP is for microburst detection on approach. MICROBURST is an airmass with a severe rapidly changing wind vector in both speed and direction.
Inertia and airmass in the extremis!
FOr the lightie driver the downwind turn is an optical illusion....happy
Your bum will tell you funny things but trust your horizon,attitude and power.
Without hijacking your thread. Heavy drivers understand what to do if encountering microburst conditions on approach to land. Heavies have(edit) lots of inertia. As the shear hits IAS changes...why is it so? Flying into the rapidly increasing airflow IAS increases...but the argument for relative airmass says there should be no change. ASI increases and aircraft starts to overshoot...pilot reduces power and lowers nose to regain approach path and then flies into the downburst, powers up and trys to arrest the sudden undershoot...so now the aircraft is nose up and under power trying to regain approach path and then aircraft flies into the strong tailwind of the microburst nose high and under full power and low energy...plenty of people have died until authorities finally believed the met guys that their aircraft can be brought down by an airmass. Me no heavy driver but it took a looong time before the authorities learnt to teach their drivers to go full power, nose up fifteen degrees and go round. More learned heavy drivers can give better description what SOP is for microburst detection on approach. MICROBURST is an airmass with a severe rapidly changing wind vector in both speed and direction.
Inertia and airmass in the extremis!
FOr the lightie driver the downwind turn is an optical illusion....happy
Your bum will tell you funny things but trust your horizon,attitude and power.
Last edited by OZBUSDRIVER; 19th Sep 2012 at 10:57.
Happy Oz.
Your point is misstated a little though. The relative airmass argument ONLY works when the airmass is stable. If you are experiencing windshear or climbing/descending into a changing wind gradient, then yes, your IAS will change. But this is not a steady airmass. In the case of a downwind turn in a steady airmass the IAS will stay the same except for the slight decrease due to the loading that happens in any turn. Anything else that happens is due, as you say, to optical illusions, and at low level, the pilot trying to fly with reference to the ground.
Your point is misstated a little though. The relative airmass argument ONLY works when the airmass is stable. If you are experiencing windshear or climbing/descending into a changing wind gradient, then yes, your IAS will change. But this is not a steady airmass. In the case of a downwind turn in a steady airmass the IAS will stay the same except for the slight decrease due to the loading that happens in any turn. Anything else that happens is due, as you say, to optical illusions, and at low level, the pilot trying to fly with reference to the ground.
Last edited by AerocatS2A; 19th Sep 2012 at 10:54.
I like this instructor's question, and that he is asking it of a 30 hour student
While I agree with the airmass bit, and that the answer the instructor was looking for was "it doesn't matter", if the clouds are cumuliform of sufficient depth they will have a ground speed associated with the lower layers they are sitting in, not the high layer you are flying in as you skim along the top ...
While I agree with the airmass bit, and that the answer the instructor was looking for was "it doesn't matter", if the clouds are cumuliform of sufficient depth they will have a ground speed associated with the lower layers they are sitting in, not the high layer you are flying in as you skim along the top ...
The BEST lesson that this thread has given is that ask a simple well explained hypothetical question and every nutter with an axe to grind, a high horse to ride or soap box to climb will feel they are obliged to reply to the question with anything but an answer.
FFS it was just a Hypothetical question to make the kid think
Elfatness enjoy the flying - it can be a great industry.
FFS it was just a Hypothetical question to make the kid think
Elfatness enjoy the flying - it can be a great industry.
Good on your instructor for making you think and understand a concept. Unfortunately this is not the place to get help. This is the place for attacks and the vomit of the weak links of this industry. Pathetic. As Ad-astra says it can be a great industry. Just keep away from this rubbish.
Last edited by sagan; 19th Sep 2012 at 19:45.
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It all makes perfect sense now, with the help of many of you! I must admit I was quite confused by the concept however now its as clear as mud
And I love flying, I wish I had started sooner! At 28 I may be pushing it to make a decent career out of it considering Im a few years away from even gaining my CPL at my current rate of training, however I'm going to give it a red hot crack!
Cheers again for the input
And I love flying, I wish I had started sooner! At 28 I may be pushing it to make a decent career out of it considering Im a few years away from even gaining my CPL at my current rate of training, however I'm going to give it a red hot crack!
Cheers again for the input
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Just to put this to bed I feel I should mention this was not a training question but a competition question for all local students. It's amazing how something fun gets turned into a cat fight (pun intended)
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Here's anothery:
Mythbusters answered it well.
Imagine a plane is sat on the beginning of a massive conveyor belt/travelator type arrangement, as wide and as long as a runway, and intends to take off. The conveyer belt is designed to exactly match the speed of the wheels at any given time, moving in the opposite direction of rotation.
There is no wind.
Can the plane take off?
There is no wind.
Can the plane take off?
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The correct answer to the original question has been given many times in this thread.
In my experience however, there are plenty of pilots, some "old and experienced" that would have answered this question INCORRECTLY.
Only in theory does there exist such a thing as "steady air mass" AerocatS2A 
The answer to the conveyor belt question is, NO - the aircraft cannot take off.
In my experience however, there are plenty of pilots, some "old and experienced" that would have answered this question INCORRECTLY.
In the case of a downwind turn in a steady airmass the IAS will stay the same ...
The answer to the conveyor belt question is, NO - the aircraft cannot take off.
Last edited by FGD135; 20th Sep 2012 at 02:43.
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Of course the aircraft can take off! The wheels will spin really fast but the aircraft will take off in essentially the same distance as if there was no conveyer belt (the wheels spinning fast may add a tiny bit of drag thus extending the ground roll by 1 to 2 feet).