djpacro

Managed to get flying today with a headset that is normally unusable in the front seat. Worked 100% with the ferrite core. For info, a simple story on the subject at http://www.mglavionics.co.za/Docs/EMI%20suppressor%20for%20VHF%20frequencies.pdf

 

 

I’m on my way home from the fly-in at Oshkosh, which, for those of you reading this in lower Slobania or the outback of Tanzania who don’t know, is the largest annual outdoor event in the world. It’s airplanes, good friends and a seemingly endless supply of porta-potties. Unfortunately, as I was driving around the far south parking area, there were none close enough to solve a pressing urinary issue. So, I solved it as only a farm kid would and right there, in front of God and everybody, I pee’d on row 147. A personal first.

 

Relax, it’s not as bad as it sounds: this was the day after the show shut down and row 147 was an easy half mile away from civilization so, I offended no one.

 

The same could not be said of my performance at the welding forum. I stood up there for an hour and a half excitedly pontificating about the glories of welding and how zen-like the skill could be. As I finished up, the large crowd applauded, I stepped down off the stage with a triumphal feeling within and someone came up to me and whispered in my ear, “Your pants are unzipped.†Ah, Man! How stupid can one person be?

 

And then there is the most classic line from the entire fly-in. I had just stepped into a porta-pottie when I heard a loud voice from the one next door. It was a woman scolding her young child. “No, don’t look down in the potty! Don’t look down!â€

 

Listen to your mom, kid. It’s good advice. And it put me in mind of the time I saw a guy coming out of a porta-potty holding his wallet by a corner as he shook it off. My mind refused to let the image of the wallet-recovery process play itself on my mental screen. Yeeeeech!

 

The possible high point of the fly-in, however, was discovering free WiFi at Arbys. It became such an after-fly-in evening ritual for me, that, if anyone was looking for me, they drove over to Arbys. How many office locations have Diet Dr. Pepper on tap, fries and apple turnovers?

 

Still, being on the road is getting really old. In July I spent 22 days on the road, and flew 23 hours of Pitts dual in six days during the short time I was home. I’m pooped! In a good sort of way, of course.

 

PS

 

Now you see why I write this blog: what legitimate magazine is going to let me write this kind of drivel? :-)

 

PPS

 

The aerial high points of Oshkosh included a B-52 making a 200 foot, pedal-to-the-metal pass, the majestic Boeing 40A, the similarly configured Zenith and a WACO ZPF (single-place WACO with a sliding canopy) that I’d love to own. I’m certain that when ("if"actually) my brain finally shows up from Oshkosh and I’m no longer in my current zombie-mode, I’ll have other, less biologically-oriented observations to offer.

 

______________________________________________________________________

 

This is from Budd Davisson's blog at Thinking Out Loud: Budd's Blog

 

 

Thanks for the reminder, OzChris. Seems to work - will investigate further.

 

 

My agent told me that the exchange rate used for calculation of GST was as of date the ship departed the USA or I could provide evidence of what I actually paid - so we did the latter.

 

 

Well, I bought a new headset and it also squeals when transmitting on frequencies 118.1, 119.1 and 119.9. Fine on 123.0 and 135.7 etc.

 

Fine in the rear seat and fine in other aeroplanes.

 

i.e. same behaviour as the good one of my old DC's.

 

Flew with someone else in the front seat - his Bose worked fine as do many other headsets. Other people have headsets which squeal like mine.

 

Experts had previously replaced the antenna cable. They had also replaced the radio with same model NARCO COM 810 (that's a separate story but didn't really affect the squeals).

 

Local radio expert mutetred something about old tube and fabric aeroplanes with modern radios.

 

http://www.aerialpursuits.com/comms/commsfaq.htm has some other ideas:

 

- yes, intercom box is mounted right below the radio

 

Don't know about the other factors except the power supply - squeals seem less at the end of a flight so after the batetry has had more charge.

 

Only other info worth mentioning is that the antenna itself is old, maybe 30 years.

 

 

US$7700 to disassemble, pack and ship in a 40 ft container from a state on the east coast of USA to Melbourne. A$2500 from the ship to the airport including customs, local cartage and agent fees - saved some as there the organisation assembling the aeroplane was a quarantine facility so the container wasn't opened until it got there.

 

Plus GST on the purchase price of the aeroplane.

 

Haven't got the bill yet for assembly, annual inspection, paint touchup, engine work and all the other stuff that you'd reckon that a serviceable airplane in the USA would have in half decent condition.

 

Didn't get an export CofA in the USA as that needed an annual also - required within 3 months (from memory) of applying for the ECofA.

 

Agent at this end was CCS - very good. Agent at the other end had arranged for new aircraft before but didnt know the rules so tried to insist on an ECofA. Guy who inspected the aeroplane was recommended to me but I think he was blind although he did an excellent job of packing in the container. Some recent aeroplanes in a container to Melbourne ended up loose in the container.

 

I spoke to others who regularly imported so learnt a lot before I did it. Was difficult to share a container with others in my case as mine was on the east coast and others were in Kansas or on the west coast. I toyed with the idea of flying the airplane west but had run out of holidays so had to get back to work.

 

My only regret is that I didn't buy 2 airplanes. My wing needed the 40 ft container but plenty of room for another. Bought when the Aus dollar was high - I needed to mention that as I normally buy at high prices and sell low.

 

 

Friend of mine with a 7ECA. Recently overhauled Lyc 0-235 so nearly 2400 hrs to run. Wings totally rebuilt recently. The rest is neat. He wants to sell but I suggested he wait until the 760 kg rule comes in. I'd like it myself.

 

 

Stall was reduced by about 8 or 9 mph

VG's can have a significant effect so I hope that some-one is looking at the effect on the design flight envelope eg http://www.recreationalflying.com/forum/general-discussion/18066-va-vso-vvvvvvvv.html

 

 

Like most places requiring prior permission - if you plan to go there and don't ring first then you're likely to get a terse greeting from the CFI or owner. On the other hand, they understand that pilots need to go somewhere in bad weather so I'm sure you'd be most welcome.

 

Years and years ago I was returning to Moorabbin from the north. Weather deteriorating and marginal VMC (low cloud and drizzle) by the time I got to Sugarloaf - not far to go to Moorabbin so tempting to keep going - I turned back to Whittlesea which had a similar reputation back then. Most welcome.

 

Friend in another aeroplane continued on - he was in a 182 while I was in an open cockpit biplane so a different perspective. While I waited for a few hours I heard on the radio about an aeroplane going down just past Ringwood (from memory). Was some-one else - my friend got back OK. Weather was bad enough without having an engine failure too - but that guy got out of it OK too.

 

 

Specific to Sensenich props but also some general stuff on page 4. Note the heading on that page is "Continued Airworthiness Requirements" - I'd ask the manufacturer of your prop for similar guidance.

 

 

I'd also recommend Punkinhead. Also Lahona - I've used them in the past as they had a template already for my airplane.

 

Funny thing is that yesterday in the mail I got a paper flyer from Bruce's Custom Covers in the USA. They must review CASA's aircraft register and saw my name on a new registration only a week or so ago. Flyer tailored to the type, prices in Australian dollars. Trouble is the statement "During the last year the U.S. Dollar has become reduced in value, relative to the Australian Dollar, by about 20%.....a great time to buy America....$1AUD=$.647USD"???

 

 

What do you fly, Ryan?

 

Ever get to the Melbourne area to have a look around at aeroplanes?

 

 

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.