First Question:
Flashing green light to a plane in the air means "Return for Landing"
&
Steady Red light to a plane in the air means "Give way continuing circling"
How are these two light signals different?
The flashing green is a local recall signal for aircraft outside of the circuit:
The steady red means, 'go around'.
Steady signals are the important ones and can all be sent by flare.
Light signals are still occasionally used at some airfields for normal movements, Old Warden for instance and some airfields where gliding is taking place.
Second Question:
What produced more severe wake turbulence? Heavy aircraft in the clean configuration or heavy aircraft in the dirty configuration?
These two type of questions(lights and wake turbulence) are found in the Operational Procedures examination and for the wake turbulence question you need to know the contents of the AIC, rather than the aerodynamic theory
The correct examination reference document for Wake Turbulence questions in the Operational Procedures examination is
http://www.ead.eurocontrol.int/eadba...2015-01-22.pdf
The above AIC was only updated a few months ago so it’s something every UK pilot & flying instructor should know about and interestingly no one quoted!.
and of course
http://www.caa.co.uk/docs/33/20130121SSL15.pdf
There is no need to go into complicated aerodynamic theory as Xrayapha has done and dug himself a hole and got some of it it wrong!
Wake turbulence is produced by the pressure differential between the lower and upper wing surfaces (induced drag) which is considered to be at its greatest at the highest angle of attack before the critical angle with flaps zeros (This is the answer the CAA want but some aerodynamicists far more knowledgable than me disagree with this)
Your two questions are typical of "exams" and "studying": ie not really relevant, at least in the way they are typically asked
These questions are completely relevant to the syllabus you are studying, making a statement like that, which may be representative of your attitude and knowledge(or lack of it in this case) encourages people to skim through text rather than try and learn and understand it.
The examination is an academic exercise designed to test your knowledge and understanding of published operational procedures which may or may not be relevant to the type of flying you are engaged in at the moment or in the part of the UK that you fly in at the moment. The misunderstanding of that relevance doesn't help with examination preparation. Treating the exams and the associated preparation as an academic exercise not only helps with the final result, it also creates a better attitude to flying in general and its the attitude you take to the aircraft that will eventually decide your destiny in it!
To treat the "heavy" one first: what people want you to know is that:
In fact what 'people' (the examiner) wants you know is that there is an AIC that deals with Wake Turbulence and that you have read it.
Now, you may ask, when might you get in a situation at your local airfield where a heavy is going to fly by "clean". And if you do, you are probably at an airfield where there is a tower with full ATC. And if there is, they will have separation minima which they will make you hold for.
A 747 recently flew into Kemble and they do not have ATC. Controllers are also just as capable of making mistakes as pilots and just relying on ATC to provide separation is hardly a thinking pilots best situation awareness plan is it?
I use this sad fatal accident on our briefings. This pilot was a panel examiner and CFI at CSE Carlisle and probably one of the UKs most experienced and qualified instructors at the time
https://assets.digital.cabinet-offic...980_G-AYMJ.pdf
As for lights.
The Air Pilot does say you can fly into Glasgow International without a radio! No-one has done that for decades! I doubt Glasgow even has light signals, but could be wrong.
Really? I would love to know where in the The UK Integrated Aeronautical Information Package (IAIP) it says that you can fly into Glasgow without a radio, perhaps it did when that document was called the Air Pilot.
What is does say is:
EGPF AD 2.20 LOCAL TRAFFIC REGULATIONS
1 Airport Regulations
(a) Use governed by regulations applicable to Glasgow CTR
and as Glasgow CTR is class D airspace you must be in radio contact with ATC ( ENR 1.4 2.4)
AD 2.20 will also tell you that there are no ground signals but there may be light signals! You would do well to actually read what you are trying to quote from!