djpacro

If that is the case - one could argue then that a light aircraft pilot doesnt need to know these theorys/principles.

I agree, pilot theory goes too far in some cases but I don't get a say in the syllabus nor do I want to waste time arguing with students about what they read in their theory notes. Just had a quick look at the CASA syllabus and that doesn't seem to be a real problem. I wonder whether the current exams require anyone to know about Bernoulli and boundary layers?

I used to like referring to sticking your hand out of a car and varying angle of attack etc but can't do that these days.

 

On the other hand, as an engineer I also need to bite my tongue as I can easily slip into stuff which is way too technical when a student asks a question.

 

 

I saw Neil fly quite a few times in the year that I spent in the UK and regardless of whether it was a display or not, Zlin or Pitts, never saw him fly anything other than a standard circuit. "something of a tribute" - nope, I don't believe that.

 

 

Re: Radio Issues...

 

Yes, others fly the aeroplane and they have new headsets which seem to work fine. Just myself and one or two others have problems.

 

I have one headset which works fine in the rear but squeals 100% when transmitting from the front.

 

Guess its time to buy a new headset and I'm inclined towards Michael's specials. Just one question - why gold-plating on the plugs?

 

 

....zero angle of attack. The lift is all due to Benouilli, Newton doesn't come into it at all.

Nope, sorry.Bernoulli and Newton are general theories which apply concurrently.

Newton explains how lift is created Lift from Flow Turning and Bernoulli simply relates local velocity to local pressure.

 

 

To follow my earlier post:

 

- Bernoulli doesn't explain the generation of lift, but does enable it to be calculated if you know the velocity distribution around the aerofoil as it simply relates local velocity to local pressure. i.e. Bernoulli applies - it is just that people have misused it.

 

- the form of the Bernoulli equation commonly seen is the incompressible version - the more general one applies to incompressible flow

 

- the stuff that we're talking about is incompressible flow - compressibility effects only become noticeable at higher subsonic mach numbers

 

- boundary layer is not really relevant in the explanation of how lift is generated i.e. you can calculate lift of a wing pretty well using inviscid flow theory. BL becomes relevant as the stall is approached.

 

 

Re: Radio Issues...

 

Thanks Michael, hadn't heard any of that from others I've asked.

 

Headset is a DC H10-40 which is 20 years old now.

 

With Xmas coming, maybe Santa will fix it - I see the ones on your website, how do you think one of those would go?

 

 

thanks Michael - I found that other thread on radio issues so I tacked my query on there

 

 

Good cue for my question, please Michael.

 

Narco COM 810 in a rag & tube aeroplane with the antenna on a ground plane on top of fuselage (interesting article about antennae on your website). Some headsets work fine and others squeal when transmitting. I have one headset which squeals on 118.1 but fine on 123.00.

 

I clean the plugs frequently but even then normally get some interference on 118.1 however often much better on return to the field later.

 

Friend with an Airtourer has a similar problem - his consistently prefers headsets with the silver looking plugs.

 

 

I look forward to contributing to your discussions and if anybody has any questions of me personally please don't hesitate to make contact either through the forum, by private message r directy through email.

Good luck with the Savage Cub!

I may take you up on your offer with a question later about interference wrt headsets and radios in rag & tube aeroplanes.

 

 

NASA has more stuff here: Beginner's Guide to Aeronautics

 

Bernoulli simply related local velocity to local pressure. Trouble is that people have invented simple theories to go with it, just for pilots, on why the velocity is what it is.

 

Personally, I like the one about male and female air particles who decide to meet up at the trailing edge at the same time.

 

Follow the links above to Factors that Affect Lift to see how lift is generated plus that Java Applet.

 

 

Most new student pilots approach this question too casually in my opinion. I.e. each lesson is only a few hundred dollars so take an appropriate amount of time to research and choose. Sit back and consider how much effort you should be putting in for a decision to spend $10,000 or so.

 

I've been concerned with some posts that I've seen where students have had numerous instructors and flown multiple types before solo – there' something wrong there. Junior instructors must have their students checked by a senior instructor as required so there's a hint – do you want a junior instructor. Walk into a flying school and enquire about learning to fly and you'll get the instructor who just happens to be there. You want the instructor who's so busy that he/she is not sitting around waiting for a stray enquiry.

 

Certainly follow up the other responses here with those schools but take more of an interest in the instructor. Talk to a lot of them – you'll be spending a lot of time with him/her and spending a large amount of money – the outcome depends on their skills/knowledge and how well you get on with them.

 

Also consider how you will use the licence when you've finished – will you want to continue at that school to hire aeroplanes and participate in their activities or not? What aeroplane have you been flying until now – probably a factor in your choice of school?

 

There is some good general advice here: [/url]

 

http://www.learntofly.com.au/choosebhfs.php

 

 

 

 

 

 

 

 

Also check out [/url]http://melbourneflighttraining.com.au/

 

 

 

 

and http://www.mfs.com.au/

 

 

 

 

 

 

Sorry Sqd Ldr, I'll get back on track with a comment on one of the queries in the original post.

 

"Of course, the aircraft designer may specify a Va speed that is greater than that minimum requirement."

Yes, the designer may choose to design the aeroplane for max control application at a higher manoeuvre speed than given by the formula in FAR 23. (refer 23.335 © (i) ) Raises an issue with the commonly regarded definition of manoeuvre speed being linked to stall speed times sqrt (design load factor).The same provision allows the designer to keep Va constant and not vary it as weight changes.

A fairly recent change to FAR 23 fixed that by introducing a new speed - VO (operating maneuvering speed) which is not greater than the stall speed times sqrt (design load factor) - refer 23.1507.

 

I've flown one or two aeroplanes where the maneuver speed is higher than Vs times sqrt (n) and they were certified prior to the introduction of 23.1507.

 

The sort of statement found in a flight manual offering guidance to pilots may be something like this:

 

"Full deflection of any one of the flight controls is authorized up to 146 mph, no matter if you are in negative or positive and with reservation that you are staying in the flight envelope."

Of course, this is not typical - that's the only one I've seen with the instruction that you must stay within the flight envelope regardless of being able to give full control deflection.

The airspeeds VD, VNE etc per FAR 23 are defined in EAS - pilots are provided info in the manual and placards in IAS (forget CAS & M for this discussion). The designer must demonstrate freedom from flutter to 25% (from memory) above flight demonstrated VD. So, he must demonstrate that taking altitude into account. If the manual/placards do not show a reduction in VNE (in IAS) with altitude then the designer would've demonstrated compliance at that VDF (EAS) at max altitude (typically allowing for max level speed at max altitude then diving to test airspeeds as VDF can only be achieved at an alititude lower than max achievable - worth remembering if horsepower is significantly increased in later models).

 

If you have a well maintained FAR 23 factory built aeroplane certified by a regulatory authority then you can be pretty confident that flutter will not occur within IAS values per the manual. (I'm unable to comment on aeroplanes that have been self-certified by the manufacturer to other than FAR 23)

 

PS - flutter (especially of ailerons) can also occur at low speeds i.e. around cruise speed and lower - several cases of this discovered during initial flight testing of prototypes.

 

 

Dan,

 

I guess you'll be flying with Gerry in the Citabria and Decathlon?

 

Have fun!

 

 

Minor additions:

 

IAS is Indicated Airspeed as given by an instrument with zero error. So what you read on your actual instrument is Airspeed Indicator Reading (ASIR). If you have a calibration of the instrument handy for your particular aeroplane you can then determine the IAS - some tests will require this to be done but for 99.9% of flying don't worry about it as the error should only be 1 or 2 kts.

 

The difference between IAC and CAS is the pressure error correction which normally arises from the static source (rather than pitot) and occurs throught the speed range. Some manufacturers are particularly good at getting the ASI to under-read at low speeds and over-read at high speeds.

 

Google should provide lots of info on this subject. (back to my meetings now)

 

 

Aviation Security[/url]

.... though that may change if GKN in Melbourne start recruiting again ...

An aero engineer from the UK on holiday in Oz dropped into my office yesterday. I told him its not a good time to be looking for a job in the aerospace industry here, Melbourne especially. But you have to remain optimistic to remain in this business so my advice, Gordon, is to check again around the middle of next year.

Page 66 of http://www.lycoming.textron.com/support/tips-advice/key-reprints/pdfs/Key%20Operations.pdf (3.5 MB) refers to what ozzie said with one difference - take it back to 1000-1200 rpm for shutdown.

 

 

So, where does this leave the earlier statement that

 

As at today: ....... There are currently four Cessna 150's on the RAAus books and they come in at 598kg

So, where does this leave the earlier statement that

 

As at today: ....... There are currently four Cessna 150's on the RAAus books and they come in at 598kg

Seems to me that the Cessna can only be made to fit current rules for RAA reg if it becomes an LSA (therefore 600 kg) but it can't get the Special CofA for LSA (as that is the responsibility of the manufacturer) so its gotta then become Experimental LSA and I don't see how it could even get into that category. Is that correct? Anyone like to explain the rules to me wrt RAA registration of Cessnas with one seat removed?

 

Incidentally, my notes of empty equipped weights of various 150's range from 505 to 513.6 kg. Aerobats range from 513.6 to 521.5 kg.

 

Sole 152 Aerobat in my little black book is 543.9 kg.

 

 

Seems to me that the Cessna can only be made to fit current rules for RAA reg if it becomes an LSA (therefore 600 kg) but it can't get the Special CofA for LSA (as that is the responsibility of the manufacturer) so its gotta then become Experimental LSA and I don't see how it could even get into that category. Is that correct? Anyone like to explain the rules to me wrt RAA registration of Cessnas with one seat removed?

 

Incidentally, my notes of empty equipped weights of various 150's range from 505 to 513.6 kg. Aerobats range from 513.6 to 521.5 kg.

 

Sole 152 Aerobat in my little black book is 543.9 kg.

 

 

I fly tailwheels not because I prefer tailwheels but because the aeroplanes that I choose to fly for other reasons happen to have tailwheels.

 

The designer chose to fit a tailwheel landing gear to save some weight and drag in the knowledge that those who would buy those aeroplanes would see it as an appropriate trade-off. In the case of the Yak 52 I'd also add that the trike version looks ungainly whereas the T/W version simply looks elegant. Others might choose the T/W configuration for rough fields - not too many places that I wouldn't go in a Husky with tundra gear.

 

 

Thanks motzartmerv, my apologies, you were right. Just spoke to Pip again briefly, who in the meantime must've doubted his own recollection as he phoned his colleague about the incident. That person had tried to alert him at the time. I won't make any excuses for him, he shouldn't have done it. If you knew Pip you'd understand how sincere he is wrt regrets.

 

Perhaps more later.

 

 

Pip would be horrified if anything he did or didn't do had such consequences.

 

I just spoke to him on the phone and he said that he always starts after turning his aeroplane side-on to the crowd line and did so at Nowra.

 

Motzartmerv, was it really Pip or some-one else in a similar aeroplane?