turboplanner

Here's a direct quote from NASA - Home, referring to the two camps - Bernoulli and Newton.

Australian Pilot magazine could have saved a lot of debate by quoting this.

"

Which camp is correct? How is lift generated?

When a gas flows over an object, or when an object moves through a gas, the molecules of the gas are free to move about the object; they are not closely bound to one another as in a solid. Because the molecules move, there is a velocity associated with the gas. Within the gas, the velocity can have very different values at different places near the object. Bernoulli's equation, which was named for Daniel Bernoulli, relates the pressure in a gas to the local velocity; so as the velocity changes around the object, the pressure changes as well. Adding up (integrating) the pressure variation times the area around the entire body determines the aerodynamic force on the body. The lift is the component of the aerodynamic force which is perpendicular to the original flow direction of the gas. The drag is the component of the aerodynamic force which is parallel to the original flow direction of the gas. Now adding up the velocity variation around the object instead of the pressure variation also determines the aerodynamic force. The integrated velocity variation around the object produces a net turning of the gas flow. From Newton's third law of motion, a turning action of the flow will result in a re-action (aerodynamic force) on the object. So both "Bernoulli" and "Newton" are correct. Integrating the effects of either the pressure or the velocity determines the aerodynamic force on an object. We can use equations developed by each of them to determine the magnitude and direction of the aerodynamic force."

As I understand it the case studies which caused HF to be introduced came primarily from dead pilots

For the masochists

Aerodynamics Lab 3 - Direct Measurements of Airfoil Lift and Drag@@AMEPARAM@@/docinfo/337576?access_key=8u2cfyt31oimq@@AMEPARAM@@337576@@AMEPARAM@@8u2cfyt31oimq

How you feeling Cralis?

Hope an aeronautical engineer will repond Shags, but I have seen formulae (carburettor designers can set the throat vacuum the same way), and know the lower the power to weight ratio, the more camber is needed. eg an Extra will fly with nearly a flat wing, but the bombers of WW2 carrying tonnes or ordnance had very pronounced curvature on the top surface. Also, if you look at the profile of the Savannah wing vs one of the faster recreational AC there is a very pronounced difference.

Could NASA have been talking about some of their re-entry aerodynamis where a lot of speed is involved?

This subject got me into hot water once at the time we started using wings in Speedway, just using flat panels with a lip down at the front and up at the rear. We began by putting them over the rear wheels thinking we would get more traction.

I made a nuisance of myself around the pits explaining Bernoulli's Theorem and how ineffective our wings would be.

My car was powered by a two stroke which fed in a massive power increase about two third of the way down the straight.

Round we rolled, the green lights came on, and two thirds of the way down the straight at around 170 km/hr my car rotated under the rear wing with the two front wheels coming up in the air just as the corner loomed up. Training kicked in and I rotated it down with brakes just in time!

I like the explanation in Stick and Rudder the author places the greatest significance on angle of attack IN ALL POSITIONS (turns, pitch etc) then adds the impact of Bernoulli's theorem.

So for example they do fly upside down but at a greater angle of attack to overcome the downward low pressure pull.

HPD, remember we are talking about Human Factors - I did say I was normally meticulous - the case had nothing to do with learning machinery operation, checklists or BAK.

It's covered under the heading "Diverted Attention" in Bob Tait's book Human Performance and Limitations which I mentioned earlier.

The training material uses real life history and actual cases and my point was that the exam could save the life of even an experienced pilot. In fact, in the section "Accidents versus experience" the training material concludes with "So you see, no matter how many hours you have in your log book, or whatever type of aircraft you fly, there's no guarantee that your next operational decision will be a good one!"

I've got a clip of a joke told by one of England's great comedians about a guy who was on the top of as building putting waste bricks into a barrel suspended on a pully. He climbs down the ladder, unties the rope......and the story goes on and on as each time one end was heavier than the other. If anyone can tell me how to attach an audio file I'll post it.

No instructor necessary - it's a question and answer exam.

Just gave an example of where it can fit in - I'm normally meticulous, but a little slip here can mean a slow reaction there so to speak.

Shags is right Cralis - this is a great way to look at things.

I'm on 36 Mhz, works OK for me, but there have been cases of unauthorised operations at a nearby oval a kilometre away taking planes down.

2.4 eliminates outside interference, but at a recent major event, several 2.4 aircraft crashed.

It turns out that current draw on 2.4 is a lot more, so everyone is going up in battery capacity - when that's done, that looks like the way of the future.

I bought the Bob Tait book Human Performance & Limitations.

Didn't think I needed it either until I got distracted in the pre-flight, forgot to dip the oil then, fortunately with instructor, encountered my first carb ice case when about to turn final.

A lot of scrambling to fix the problem and a very red face!

Jet Fuel

Bud and Jim were a couple of drinking buddies who worked

as aeroplane mechanics in Sydney.

It was Christmas, all the planes were out, the airport was fogged in and they had nothing to do.

Bud said, "Man, I wish we had something to drink!"

Jim says, "Me too. I've heard you can drink jet fuel and get a

buzz. You wanna try it?"

So they poured themselves a couple of glasses of high-octane

hooch and got completely smashed.

The next morning Bud wakes up and is surprised at how good

he feels. In fact he feels great, no hangover, no bad side

effects.

Nothing at all.

Then the phone rings...its Jim.

Jim says, "Hey, how do you feel this morning?"

Bud says, "I feel great. How about you?"

Jim says, "I feel great, too. You don't have a hangover?"

Bud says, "No, that jet fuel is great stuff - no hangover,

nothing. We ought to do this more often."

"Yeah, well there's just one thing..."

"What's that?"

"Have you farted yet?"

"No....."

"Well, dont, 'cause I'm in Adelaide..."

Congratulations, but don't land in one of those prickly trees or stop at an intersection!

Tie 'em down

Sometimes happens on the road as well, reminds me of the story an old cattleman told in an outback pub.

"I used ter ave two planes, a little one and a big one to go to town.

"Hit the hangar with the big one one night, so I put it on a semi and sent it to town to be fixed.

"The driver didn't tie er down well enough and she fell orf.

"The road was dusty and he didn't see.

"Drug er for 8 mile and then she was ******.

"Only got the little one now."

Stick and Rudder

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Brilliant read, hard going, but you'll never do low swoops and wingovers at low level after reading it

You haven't lost the Tiger Moth have you????

K-Man:had a look for the quote, couldn't find it, but how's this:

"But when the pilot is already flying at near top speed, where induced drag has almost disappeared and parasite drag is the only important type of drag, and if he then tries to fly a little faster, he does get the full working of the cube law straight in the neck"

Ian, I used to do what you did, nose down back to the airfield = less hours until I read "Stick and Rudder" by Langewiesche - he more or less covers this subject.

And the restaurant is worth flying from Darwin for.

Take out Life Insurance to cover the future of your kids, then relax because its a lot more likely that you and your wife will be driving home from a party and be killed by a drunk. I've had the same feelings and they are not easy to shake off, but I cold heartedly assessed the risks. There are some things I haven't done because they ARE dangerous, but I drove in Speedway for about 12 years because it was actually safer than highway driving. Good luck in shaking it.

BLA82, the RAA regulations as they stand have resulted in an exceptional safety record, which has not been matched by many other activity sectors in the community.

The unfounded speculation and preaching you started is now on the public record for any lawyer or journalist to use should an unfortunate case ever come up, and remember this type of incident is almost non existant in flying.

Just get on to Google and search for "Pilot Incapacitation" and this tread comes up at No6 with its lurid but medically and statistically unsupported themes that RAA is riddled with refugees from the GA system who can't obtain medicals etc.

We have an excellent Administration at which level statistics can be analysed to see where the biggest risks are, and management action can be taken after obtaining professional advice, and that's the more appropriate forum for this subject.

With around 10,000 RAA members and the safety statistics we have, our regulations appear very sound, and it's wrong to compare them with other forms of aviation where different performance requirements occur.

Congratulations on your responsible attitude to flying Mick and the professional way you minimise risk. We don't have to wait for accidents to happen, the historic statistics are already there and fatalities caused by medical conditions have a minute representation. Behavioural issues dominate and that's where we should be focused.

Over the years I've read many reports of fatalities where "the pilot continued on into conditions which did not meet Visual Meterological Conditions", and I was sent into marginal conditions myself once as a result of a non standard code which was part of the Telex based planning tool provided by CASA's predecessors apparently when Biggles was active, but that's another story.

We've all been told never to fly into cloud because we'll lose control and die, and the technical reasons for this are well explained.

What it not as well explained are the pointers which would either keep you on the ground in the first place, or ensure you get out of there in plenty of time for an uneventful landing.

Would appreciate tips from our experienced pilots on how they stay safe in the face of variable weather reports and conditions which are not always easy for the occasional flier to identify.

Question 3 - It only happens to the nervous ones who hesitate, wait till they see the neighbour taking the crop off, and start the harvest on the back end of a High, or it may be that they strayed from the thread.