Love this german engineering

[facthunter]

On the gravity and vacuum thing, Gravity is a force acting on a body. Mass X gravitational force gives weight Mg = W.

 

In anything but a vacuum a falling body will reach a terminal velocity where Mg = drag, at some stage.

 

In a vacuum a feather will fall at the same rate as a ball of lead. Both would accelerate at 32 feet per,second each second.

 

In a gas ie the atmosphere, there will be increasing drag which will slow the rate of acceleration until it reaches a state of no acceleration ie the terminal velocity. The thickening of the atmosphere complicates this example as you have a reducing terminal velocity as you descend.

 

If you are the occupant of said vehicle, once it reaches terminal velocity you will weigh 1G because you are not affected by the drag (being enclosed) and you are still affected by the force of gravity which is trying to accelerate you at 32 ft/sec/sec. The vehicle is not accelerating anymore, due to drag. Nev.

 

 

[Marty_d]

Nev, I can't blame the wine as I've only had 1 glass, so it must just be limited intellect. Trying to wrap my mind around the terminal velocity in atmosphere concept and coming up short. If your theoretical gimbal-mounted anti-grav device had variable power, so for example you could dial it up to say 5G in a forwards direction, how do you determine what your terminal velocity is, given that the shape of your craft could be a very streamlined needle?

 

To my knowledge 1G = around 9.8 m/s^2, so 5G would be about 49 m/s^2, or in common terms, "fair honking pretty bloody quickly".

 

In fact given that the only limiting factor would be atmosphere, it seems that the best way to get anywhere reasonably far away would be to accelerate vertically until into space (preferably missing the satellites and other associated junk), turn at speed when well clear of everything, then back into the atmosphere when somewhere over your target.

 

All of which suggests that the most important thing in the new design may be good heat shielding at the front.

 

Phil, I'm in awe of the quality of your past pen pals, and if you tell me that Sir Terry Pratchett was among that august company I will possibly be prostrated with shock.

 

 

[Phil Perry]

Regrettably,. . . . .no.

 

And I apologise unreservedly if my correspondence had anything to do with the demise of my herein aforementioned worthies. . . . . .

 

 

[Phil Perry]

Hmm, seems like you're a dangerous person to correspond with. Everyone you write to ends up dying.

คนที่โง่มากที่ชอบเครื่องบิน

 

Sorry,. . .can't help it.

 

 

[Phil Perry]

Leaving the esoterica aside

Hiya Jaba . . .

 

Esoterica. . . now that would have been a much better moniker for an aircraft project in the UK around 13 years ago, the machine was called OPTICA. Have a google at it. . . we discussed this one last year on this forum actually. It was being evaluated by a few Police forces in the UK to replace helicopters in certain circumstances, as it was much cheaper to buy / run, and it could also fly moderately slowly, ie around 55 Miles per hour, carrying a pilot and observer in a bubble type cockpit a la helicopter, ideal for aerial search ops etc. It died when the factory, including all the tooling and a couple of complete aircraft burned down in suspicious circumstances.

 

Now if some enterprising individual had though of hanging some road gear on it,. .this could have been interesting. . . but alas, it never was. although it would NOT satisfy Nev's criteria regarding parasitic bits hanging in the airflow during flight mode. . . . If Avocet Mike hasn't seen this yet, I know he'd appreciate the design . . . due to the fact that it is unusual in a lot of respects . . . .(?)

 

 

Edgeley EA7 Optica . . . esoteric but not as much as some of Burt Rutan's ideas. . . .

 

 

[pmccarthy]

I danced with a man, who danced with a girl, who danced with the Prince of Wales. I feel closer to Isaac Asimov than ever before, the hero of my youth.

 

On anti gravity, don't forget that you must input enough energy to gain the potential energy increase with every metre of height, including efficiency losses. And as you descend, the potential energy has to be converted to velocity, or heat, or somehow stored. Otherwise an anti gravity machine is a perpetual motion machine, defying physics.

 

 

[Phil Perry]

I danced with a man, who danced with a girl, who danced with the Prince of Wales. I feel closer to Isaac Asimov than ever before, the hero of my youth.On anti gravity, don't forget that you must input enough energy to gain the potential energy increase with every metre of height, including efficiency losses. And as you descend, the potential energy has to be converted to velocity, or heat, or somehow stored. Otherwise an anti gravity machine is a perpetual motion machine, defying physics.

Yeah Yeah Yeah,. . . . . . we think we know all that . . . . . ( We think. . .therefore,. . .we are. . . . .) and your point is . . . .? what about antigraviticvelocity batteries, . . .? . . . .sorted.

 

Yes,. . .the Deane drive ( disproved ) . . . .the ONLY perpetual motion machine in the Western World at the moment, is run by the Inland Revenue. . . . . .

 

 

[facthunter]

To make one thing clear, I'm not designing a vehicle, in this terminal velocity thing, I'm just attempting to illustrate a principle.

 

Energy management and understanding is part of flying. It's probably not dealt with enough.

 

Height is potential energy. A distance over which a force (gravity) can apply to an object.. That is the definition of work W=F times S ( Force x distance)

 

It takes the same to get you up there. Surplus power allows a height gain. (which you can recoup in the glide). Gravity replaces power as the force available to overcome drag.

 

Equilibrium in level flight with adequate power available, power equals drag and lift equals weight,

 

Terminal velocity is equilibrium in a vertical descent, where weight equals drag.

 

You can have energy as a result of your velocity. (Kinetic) This behaves as a squared rule . MVsquared whereas potential energy ( energy of position) is distance x force.

 

In a flying sense if you are LOW and SLOW you don't have a lot going for you. with your energy options..Nev

 

 

[Head in the clouds]

Energy management and understanding is part of flying. It's probably not dealt with enough.

Ain't that the truth.

 

Possibly one of the most valuable lessons I ever learnt about flying was drummed into me by a good friend and accomplished instructor -

 

- think ahead for power requirements.

 

'Power' being available from any of a number of possible sources - engine, height, speed, rising air ... and as you point out Nev, a shortage of all them leaves you in an unenviable position.

 

 

[Marty_d]

Otherwise an anti gravity machine is a perpetual motion machine, defying physics.

I plan to offset my gravity use by reducing the gravity of nearby planets. Physics is safe.

 

Phil, I believe the Optica was in use by the WA police force, at least so I was told. Can anyone confirm or deny?

 

 

[Phil Perry]

Don't honestly know haw many were made / sold Marty. . . I guess it's on record somewhere, maybe wiki. . . I got that pic from my own archives, posted same one before. . . .

 

 

[Garfly]

A hiccup along the way. Test pilot/designer saved by BRS.

 

 

http://www.avweb.com/avwebflash/news/Aeromobil-Flying-Car-Crashed-Pilot-OK-224052-1.html

 

 

[Marty_d]

They have a strange definition of "only partially damaged".

 

I'm with Nev on this one. Flying car simply gives you the worst of both worlds.

 

 

[facthunter]

Looks an outrageously expensive design concept. Nev

 

 

[Phil Perry]

They have a strange definition of "only partially damaged".I'm with Nev on this one. Flying car simply gives you the worst of both worlds.

It's the old story again I think Marty,. . . ."ONE DAY. . . . .Everyone will have a flying car. . . . . . ." "We won't need freeways any more. . ." No they bloody well WON'T . . . .it is a ridiculous idea,. . . not EVERYBODY has the wherewithall to fly at all,. . . . I feel sorry for a guy at my airfield who has just completed his twenty seventh hour of flight training in an EV97 Eurostar, and says that he is "Nowhere near". .. going solo in the foreseeable future,. . . I've watched him in the circuit, watched the poor guy trying his best to land it,. . .even in dead calm conditions,. . .he is obviously not comfortable with it. . . . and I have to admit, he could be right,. . . .WELL,. . . .I wonder why the FI hasn't had a quiet word and suggested that he take his Wife on a World cruise, or buy a caravan, . . .a boat, a HArley DAvidson, if he wants some expensive thrills. . .but pack it in for heaven's sake and stop wasting your hard earned . . . . . not everyone is suited to flying. . . . . ( Evidently ) I can see the Instructor's financial angle, at £110.00 per hour. . . but I still think he is a prat. . . . .

 

I hate to seem callous and nasty about this one,. . .and yes, it is one of my many hobbyhorses,. . . . a very good friend of mine, local woodsmith, makes boat rudders, centreboards, and the best toilet seats i've ever seen, all out of a dozen different kinds of timber all glued together and then machined. . . .real pleasure to go to the bog,. . . .he had been "Taught" at Halfpenny Green Airport, down the road from where I'm domiciled,. . he had NOT been sent solo,. . .and had completed thirty eight hours of training in a C-152, and was told that he would not be given a flight test, as his circuit rejoins needed work. . .! ! ! For chrissake !

 

I drove him to another airfield ( Shobdon, near the SAS base in Herefordshire ) and the CFI, a mate of mine named Dennis Davies, took him on what was supposed to be an "Evaluation" flihgt. . .to see what he knew. After landing, . . .Dennis gave him a pass slip and said, bugger off and apply for your PPL.

 

I wonder how often this sort of thing happens in the training industry ( Where are yer Merv . . .? ! ! )

 

Yes,. . I realise that these two stories are at the opposite ends of the training spectrum,. . .but. . . . .sheesh. Makes you wonder how many promising students give it neck due to innappropriate instruction. . . .?

 

NOW,. . . multiply that by a few hundred thousand people, to whom the concept of the FLYING CAR is obviously aimed,. . . . . gawd help us. . . . .let's hope the industry comes up with FLY BY WIRE cars, just like the groundling "Driverless" cars before that happens. . . . .!

 

 

[facthunter]

Instructors and organisations have a big responsibility to do the right thing.

 

Don't dumb it down too much . The student may die one day because of what you didn't teach .

 

Don't take the peoples money when they will never be safe. Some shouldn't be there at all.

 

Never get angry with a student. It's THEIR money and you are not professional if you do. If you can't keep your cool,consider whether YOU should get another job too. Nev

 

 

[Geoff13]

And then on the other hand Phil, the guy is obviously aware that he is not getting it as he told you as much. Maybe he is aware that he will never get it but is still happy to come out once a week and have an hour or so in the air even if it is beside an instructor. Maybe the Instructor has had that conversation and they have determined that an hour sitting beside the instructor is better than an hour at the pub.

 

I know many people who should not be let loose with a shopping trolley let alone a car or heaven forbid a flying car. That doesn't mean that development should or will stop.

 

 

[Phil Perry]

Yes Nev,. . .sorry about the rant. . .( again ) . .I think the Germans had the right idea with their intensive youth glider training i the early 1930s, they soon differentiated between the students with an innate ability to learn the craft, and thos who couldn't, for their forthcoming Luftwaffe. . . and it certainly worked for them,. . .well,. . .for some of the conflict anyway. . . .

 

Catch 'em young. . .should be the clarion call, but nowadays the young are too involved with iPhones, facebook, tattoo parlours and weird music in their daft little hot cars with all the suspension lowered so they can't drive over speed humps. . . . . The ATC cadets don't get any flying any more due to Govt. cuts,. . .so there is really no way to get the kids interested in flying. . . .my airfield is full of miserable old fartz . . . .as is the expected result . . . .

 

***Edited to add. . . .If any of our club members want to give a kid under 16 a flight, they have to be CRB checked first,. . . to make sure they are not Kiddie Fiddleers,. . .this takes up to three months nad there are costs attached. . . . . . nightmare.

 

 

[Phil Perry]

And then on the other hand Phil, the guy is obviously aware that he is not getting it as he told you as much. Maybe he is aware that he will never get it but is still happy to come out once a week and have an hour or so in the air even if it is beside an instructor. Maybe the Instructor has had that conversation and they have determined that an hour sitting beside the instructor is better than an hour at the pub.I know many people who should not be let loose with a shopping trolley let alone a car or heaven forbid a flying car. That doesn't mean that development should or will stop.

Yes Geoff,. . .I appreciate your comments, but that wasn't really what I was getting at,. . .but no matter. . . .it's still sad. BTW,. . .the young bloke I mentioned had said Nothing negative to me about his training, other than the fact that he loves every minute of it, and at the moment, he can afford it,. . . . so fair enough,. . .let him have his two lessons per week,. . .I just hope that he will click, and realise his dream. . . . . . He is a long distance truck driver Geoff,. . . . for one of the Belgian multi nationals,. . .he says he only thingks about flying and bacon sarnies all day. . . .!

 

 

[facthunter]

That's true Geoff , and people should make space for people like that in an aviation "community". As long as they aren't strung along thinking they will solo soon. Nev

 

 

[Marty_d]

Interesting point Phil, I reckon the developments in driverless cars in the next few year will change road transport beyond recognition. Saw in the news that there's now a self-driving truck (semi-trailer) authorised for use in the US - but only with a "backup" human at the controls should anything go wrong.

 

With many cities now having 1.5 - 2 hour commutes, I reckon many people would like a car where they can swing the seat around and do some work/reading/whatever, while the car does all the stressful stuff.

 

Not to mention it'd be bloody handy after a few at the local. No more worries about random breath testing.

 

In regards to the age of recreational pilots it's not only the other attractions but the cost. With people in their 20's trying to borrow upwards of half a million to buy a house, or spending a heap on rent every week, flying would be a long way down the list of essentials. Not to mention kids are expensive and time consuming too.

 

 

[facthunter]

Phil you aren't miserable etc You just give a good impression. Nev

 

 

[Phil Perry]

Phil you aren't miserable etc You just give a good impression. Nev

Maybe not,. . . .but I definitely qualify as the archetypal Whingeing Pom. . . . . . .

 

 

[microman]

Yes Nev,. . .sorry about the rant. . .( again ) . .I think the Germans had the right idea with their intensive youth glider training i the early 1930s, they soon differentiated between the students with an innate ability to learn the craft, and thos who couldn't, for their forthcoming Luftwaffe. . . and it certainly worked for them,. . .well,. . .for some of the conflict anyway. . . .Catch 'em young. . .should be the clarion call, but nowadays the young are too involved with iPhones, facebook, tattoo parlours and weird music in their daft little hot cars with all the suspension lowered so they can't drive over speed humps. . . . . The ATC cadets don't get any flying any more due to Govt. cuts,. . .so there is really no way to get the kids interested in flying. . . .my airfield is full of miserable old fartz . . . .as is the expected result . . . .

 

***Edited to add. . . .If any of our club members want to give a kid under 16 a flight, they have to be CRB checked first,. . . to make sure they are not Kiddie Fiddleers,. . .this takes up to three months nad there are costs attached. . . . . . nightmare.

Phil - your post struck a chord - our club has 180 members - average age 56! Every year we talk about how can we get young people into flying but it just doesn't happen - as you say they are too busy with their hot cars and other hobbies. We have just taken the local ATC Squadron under our wing (like you guys only very limited Govt funding) - providing some free flying in the club aircraft, a scholarship for a chosen pupil to go right through to solo, inviting them to our social and flying events, and anything else we can think of - at least we will be targeting aviation-minded kids. We would have crawled over barbed wire to go flying when we were young but times have clearly changed.

 

 

[bexrbetter]

Every year we talk about how can we get young people into flying but it just doesn't happen ..... We would have crawled over barbed wire to go flying when we were young but times have clearly changed.

Ya think?