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220km/h cruise on a 50HP engine?


Marty_d

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220km/hr is only 118kts.

 

So some numbers follow...

 

Scott Winton Opel; 40hp = 280 kmh (151kts)

 

Verhees Delta; 50hp = 220 kmh (118kts)

 

Arnold AR-5; 62hp = 213 mph (185kts)

 

5flbeau.jpg.b2d37dad30d2212dc3a17804ec694c3f.jpg

 

The Arnold AR-5 was powered by a Rotax 532, then later a 582, and weighed less than 300kg!

 

Have a look at; http://www.ar-5.com/kitcarm93.html

 

 

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220km/hr is only 118kts.So some numbers follow...

Scott Winton Opel; 40hp = 280 kmh (151kts)

 

Verhees Delta; 50hp = 220 kmh (118kts)

 

Arnold AR-5; 62hp = 213 mph (185kts)

 

[ATTACH=full]23577[/ATTACH]

 

The Arnold AR-5 was powered by a Rotax 532, then later a 582, and weighed less than 300kg!

 

Have a look at; http://www.ar-5.com/kitcarm93.html

Thanks Pylon, interesting read!

 

 

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The AR-5 is a gorgeous aircraft, but I have to say, that Delta looks really easy to build for not much money. A few sheets of aluminium & a handful of rivets. With the right engine to get the weight down a little, it would qualify under 95.10. Their website shows a lot more about it, including folding wings for trailering.

 

 

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You would want to know how it behaves in turbulence and at low speeds. Its a lot of leading edge sweepback for a low speed plane.( 110 Knots is not fast) It would have to be aerodynamically clean though. Nev

The website has a handling report written by a high hour pilot that is reasonably complimentary, he highlights a couple of small issues.

 

 

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220km/hr is only 118kts.So some numbers follow...

Scott Winton Opel; 40hp = 280 kmh (151kts)

 

Verhees Delta; 50hp = 220 kmh (118kts)

 

Arnold AR-5; 62hp = 213 mph (185kts)

 

[ATTACH=full]23577[/ATTACH]

 

The Arnold AR-5 was powered by a Rotax 532, then later a 582, and weighed less than 300kg!

 

Have a look at; http://www.ar-5.com/kitcarm93.html

Outstanding performance and design!

 

 

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You would want to know how it behaves in turbulence and at low speeds. Its a lot of leading edge sweepback for a low speed plane.( 110 Knots is not fast) It would have to be aerodynamically clean though. Nev

110 knots sounds fast to someone building a 701. 008_roflmao.gif.692a1fa1bc264885482c2a384583e343.gif

 

That Scott Winton Opel just looked wrong to me... a square slab of flying wing, looked like it'd get very twitchy very easily (just an impression NOT backed up by any in-depth design knowledge!)

 

Swept-back flying wings though I find fascinating, especially the strength you would be able to get into the wing with such a massive thickness and chord at the root.

 

 

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AS you say plenty of wing thickness for strength and storage but with that amount of leading edge sweepback it might exhibit too much lateral stability and tend to dutchroll. Nev

Perhaps if it was a swept flying wing but not likely as a delta. The l/e sweep, significant fin and lack of side area forward of the CG would give it good directional (longitudinal) stability and the almost total lack of dihedral would result in very little lateral stability so it should never enter the dutch-roll excitation zone which requires the lateral stability to considerably exceed the longitudinal stability.

 

 

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Another thing I like about this particular aircraft is the single retractable wheel. As with others - such as the Europa - it seems to make sense to have one beefed-up, retractable wheel on the centre line where you have the strength of the fuselage to mount directly to. Other obvious advantages: easily retracted, weight saving (even a beefed-up single leg is going to be lighter than 3 full sized legs/wheels), and if the wheel protrudes slightly when retracted, at least a wheels-up (sorry, "wheel-up") landing is not going to be as hard on the belly...

 

I guess the disadvantage is you'd need to make damn sure your wings are level when landing.

 

 

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Perhaps if it was a swept flying wing but not likely as a delta. The l/e sweep, significant fin and lack of side area forward of the CG would give it good directional (longitudinal) stability and the almost total lack of dihedral would result in very little lateral stability so it should never enter the dutch-roll excitation zone which requires the lateral stability to considerably exceed the longitudinal stability.

HITC.

Directional stability is stability in YAW.

 

Longitudinal stability is stability in PITCH.

 

They are not the same!

 

Please clarify your post.

 

 

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220km/hr is only 118kts.So some numbers follow...

Scott Winton Opel; 40hp = 280 kmh (151kts)

 

Verhees Delta; 50hp = 220 kmh (118kts)

 

Arnold AR-5; 62hp = 213 mph (185kts)

 

[ATTACH=full]23577[/ATTACH]

 

The Arnold AR-5 was powered by a Rotax 532, then later a 582, and weighed less than 300kg!

 

Have a look at; http://www.ar-5.com/kitcarm93.html

And where are the Position Error calibration figures? (See http://www.casa.gov.au/wcmswr/_assets/main/rules/1998casr/021/021c40.pdf

 

 

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HITC.Directional stability is stability in YAW.

Longitudinal stability is stability in PITCH.

 

They are not the same!

 

Please clarify your post.

No - not quite right as I understand it. Directional stability is the stability associated with the aircraft wanting to return to its direction of travel. That might require it to return there by a pitch change or a yaw change (or both) according to whether the upset or disturbance has changed the direction that the aircraft is pointing in its x axis or its y axis (or both).

 

In other words if the aircraft is pointing where it is heading (z axis) and then gets upset by turbulence (say) such that the nose rises (y axis) and the nose then seeks to return so as to point in the direction of travel, then the aircraft has positive pitch directional stability. Similarly if the aircraft is upset such that the nose moves to either side of the direction of travel (x axis) and the nose then seeks to return so as to point in the direction of travel, then the aircraft has positive yaw directional stability.

 

I should not have put the word longitudinal in parenthesis, it confused the issue because 'longitudinal' stability is pitch and yaw directional stability combined, otherwise, by your reasoning we would have lateral stability for roll, longitudinal stability for pitch, and vertical stability for ... what ... yaw? Because the three axes are lateral, longitudinal and vertical - not lateral, longitudinal and directional.

 

 

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No - not quite right as I understand it. Directional stability is the stability associated with the aircraft wanting to return to its direction of travel. That might require it to return there by a pitch change or a yaw change (or both) according to whether the upset or disturbance has changed the direction that the aircraft is pointing in its x axis or its y axis (or both).In other words if the aircraft is pointing where it is heading (z axis) and then gets upset by turbulence (say) such that the nose rises (y axis) and the nose then seeks to return so as to point in the direction of travel, then the aircraft has positive pitch directional stability. Similarly if the aircraft is upset such that the nose moves to either side of the direction of travel (x axis) and the nose then seeks to return so as to point in the direction of travel, then the aircraft has positive yaw directional stability.

 

I should not have put the word longitudinal in parenthesis, it confused the issue because 'longitudinal' stability is pitch and yaw directional stability combined, otherwise, by your reasoning we would have lateral stability for roll, longitudinal stability for pitch, and vertical stability for ... what ... yaw? Because the three axes are lateral, longitudinal and vertical - not lateral, longitudinal and directional.

Nope. Aircraft stability is usually defined in relation to "wind axes" - not axes fixed in space relative to the Earth. See http://en.wikipedia.org/wiki/Aircraft_principal_axes

 

 

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Nope. Aircraft stability is usually defined in relation to "wind axes" - not axes fixed in space relative to the Earth. See http://en.wikipedia.org/wiki/Aircraft_principal_axes

Nope - not where discussion of stability is concerned. And it's a sad day when Wikipedia is considered to be a principal reference on any matter, let alone aeronautical engineering. The reference in the link you supplied has nothing to do with the discussion which is about stability axes not wind axes - from your own reference - "Yaw axis is a vertical axis through an aircraft, rocket, or similar body, about which the body yaws; it may be a body, wind, or stability axis." Not and stability axis.

 

I have no interest in arguing the semantics with you Daffydd, I think the answer I provided for DWF is perfectly clear and provides an understanding of the situation, your argument does nothing to help and a lot to confuse and is clearly made simply for argument's sake.

 

 

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HITC.

 

I think you are confusing the issue and/or are confused about aircraft stability theory.

 

I cannot seem to capture the link to put here, but if you go to

 

raaus.com

 

- safety

 

- John Brandon's fly safe tutorials

 

- scroll down to and click on "flight theory"

 

- and select "stability"

 

you will find the conventional explanation of aircraft Stability.

 

This is similar to the explanation you will find in most text books. 072_teacher.gif.7912536ad0b89695f6408008328df571.gif

 

Sorry to drag this thread off topic but I think it is important that student pilot (and other) readers are provided with access to the generally accepted view on stability.

 

It is the explanation that is (or should be) given to all student pilots in their second (or so) lesson - Straight and Level.

 

 

 

DWF 080_plane.gif.36548049f8f1bc4c332462aa4f981ffb.gif

 

 

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HITC.

I think you are confusing the issue and/or are confused about aircraft stability theory.

 

I cannot seem to capture the link to put here, but if you go to

 

raaus.com

 

- safety

 

- John Brandon's fly safe tutorials

 

- scroll down to and click on "flight theory"

 

- and select "stability"

 

you will find the conventional explanation of aircraft Stability.

 

This is similar to the explanation you will find in most text books. 072_teacher.gif.7912536ad0b89695f6408008328df571.gif

 

Sorry to drag this thread off topic but I think it is important that student pilot (and other) readers are provided with access to the generally accepted view on stability.

 

It is the explanation that is (or should be) given to all student pilots in their second (or so) lesson - Straight and Level.

 

 

 

DWF 080_plane.gif.36548049f8f1bc4c332462aa4f981ffb.gif

HITC is a excellent Ultralight pilot who was also excellent instructor in Ultralights and he spent many years as a commercial helicopter pilot. I reckon he would have a fair idea on aircraft stability. Just sayin

 

 

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HITC is a excellent Ultralight pilot who was also excellent instructor in Ultralights and he spent many years as a commercial helicopter pilot. I reckon he would have a fair idea on aircraft stability. Just sayin

Helicopters are just about as unstable an aeronautical conveyance as one can get. 075_amazon.gif.0882093f126abdba732f442cccc04585.gif :rotary:003_cheezy_grin.gif.c5a94fc2937f61b556d8146a1bc97ef8.gif

Just sayin 001_smile.gif.2cb759f06c4678ed4757932a99c02fa0.gif

 

 

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