The Dreaded V-Tail and my part in its downfall.

[Hawaii Sloper]

I want to see a Konrad Design!

C'mon Konrad -Money? Mouth?

Show everyone that you have been right all along, dude!

Put down the lines and justify.

No excuses, not "its not my job", no "I'm not a designer" etc etc

Doc.

 

[gp49]

Moly GP - I didn't knw that.

The only time we tried to get the Destiny going was along a slope but in really light winds, and it didnt really like it.

Doc.

Actually i stand corrected:

Carbon wing Destiny: 301mph
Glass Destiny: 213 mph
Mini Destiny (micro Floh): 187 mph

We have flown the micro Floh in 10-12 mph ( good lift ) and its a great flyer. Our carbon Destiny is a finicky beast. It likes to have its way with the pilot in the turns. Good thing Alex is young and has good reflexes.

 

[Konrad]

I want to see a XXXXX Design!

C'mon Konrad -Money? Mouth?

Show everyone that you have been right all along, dude!

Put down the lines and justify.

No excuses, not "its not my job", no "I'm not a designer" etc etc

Doc.

Here and here and here as they pertain to the issue at heart.
You should be able to see my engineering attempts at redesigning the problems with flap actuation, stabilizer actuation along with my incremental and iterative approach to the inherent instability issue with the Jimmy Durante nose, using tools most modelers would have available..

Guys don’t fall for the straw man argument. This isn’t a Trump rally. The point of this thread was the Hammond V-tail and its reputation. And to a lessor extent my involvement, if any, in perpetuating this reputation. I’m probably the only guy in the world that has both of Hammond's V-tail designs in flying shape and fly them both in rapid succession. So it is natural for folks to ask me about them. Particularly as they have heard so much about the Strega’s V-tail alignment issues. In the course of the discussion I may mention that the issue with the Redshift isn’t the V-tail but rather the front side area and the destabilizing effect of forward side area.

Now here's an idea if I can’t get a suitable margin of stability out of the molded Redshift parts. Graft on a set of V-tail with the appropriate wetted area. I wonder if SoaringUSA has any left over parts parts used to support the sales of the Strega. I do have enough Redshift carcasses to work with.

Design is so much more than an artists interpretation. The key to good design is system integration. This is often known as form fit and function. Here the function, effect of side area on stability doesn’t look to have been fully taken into account.

As I see Hammond is loosing perspective I will leave the subject saying that in the market place the Hammond V-tail has a very bad reputation. I think this is a bit unwarranted when looking at the true cause of the reported stability issues. I’m sorry Hammond chosen to shoot the messenger in his first post.

 

[Konrad]

They did go the easy way out and not made tail at least bigger, but that Destiny is still a hoot to fly ( as long as you remember it's quirks) The micro Floh is a very nice flyer too. Even with the known problems the Destiny speed record is just below 290mph (!?)

An extensively reworked Destiny!

It is fun to see what folks can do with a sow's ear.

 

[Doc J]

Here and here and here as they pertain to the issue at heart.
You should be able to see my engineering attempts at redesigning the problems with flap actuation, stabilizer actuation along with my incremental and iterative approach to the inherent instability issue with the Jimmy Durante nose, using tools most modelers would have available..

Guys don’t fall for the straw man argument. This isn’t a Trump rally. The point of this thread was the Hammond V-tail and its reputation. And to a lessor extent my involvement, if any, in perpetuating this reputation. I’m probably the only guy in the world that has both of Hammond's V-tail designs in flying shape and fly them both in rapid succession. So it is natural for folks to ask me about them. Particularly as they have heard so much about the Strega’s V-tail alignment issues. In the course of the discussion I may mention that the issue with the Redshift isn’t the V-tail but rather the front side area and the destabilizing effect of forward side area.

Now here's an idea if I can’t get a suitable margin of stability out of the molded Redshift parts. Graft on a set of V-tail with the appropriate wetted area. I wonder if SoaringUSA has any left over parts parts used to support the sales of the Strega. I do have enough Redshift carcasses to work with.

Design is so much more than an artists interpretation. The key to good design is system integration. This is often known as form fit and function. Here the function, effect of side area on stability doesn’t look to have been fully taken into account.

As I see Hammond is loosing perspective I will leave the subject saying that in the market place the Hammond V-tail has a very bad reputation. I think this is a bit unwarranted when looking at the true cause of the reported stability issues. I’m sorry Hammond chosen to shoot the messenger in his first post.
View attachment 12519View attachment 12520

Just as I thought.

Doc.

 

[Wayne]

I hate the Destiny.. That is just me. They are a very old design that I feel should have been pulled from, production in the 90s. There are much much better aircraft available.

I know some folks love 'em.

Konrad I fully disagree with you. But I guess I'm not an expert and have no idea what I am talking about and can't be trusted because I am a salesman.

Can we please stop bitching about stuff and focus on brighter topics?

 

[Konrad]

I hate the Destiny.. That is just me. They are a very old design that I feel should have been pulled from, production in the 90s. There are much much better aircraft available.

I know some folks love 'em.

Konrad I fully disagree with you. But I guess I'm not an expert and have no idea what I am talking about and can't be trusted because I am a salesman.

Can we please stop bitching about stuff and focus on brighter topics?

Fully disagree? So you think there might be an issue with the V-tail? I've try to clearly state the issue isn't with the V-tail rather the relationship between the front and rear vertical area, be it a cruciform tail of V-tail.

As to being a salesman I see you as an exemplary business man of high ethical standing. Actually you are very good as assessing the needs of the customer and offering solutions even if you don’t carry the product.

All the best,
Konrad

 

[ORRich]

Personally I would like to see the following - so if there is a way to keep everyone happy:

1) A separate channel in this forum for Aerodynamics - anyone who wants to geek out on fluid dynamics and reynolds number can go there
2) If anyone (not picking on Konrad) want to ask a real question about a specific model, be it a critique, improvement, question etc: just do it via private DM - just to make sure we're not trying to show our chops in front of the studio audience (and I'm not necessarily saying Konrad does this, but by DMing someone directly, there is no doubt that the question is for real)- the reason I say this is that Doc seems to be one of the few (if not only) designers on this forum - so if you wanted to ask another designer, you'd have to email them vs post in this forum - so that should keep things fair-

Not trying to fan flames but just trying to appease all -
When I see a post title around REDShift etc, (as a newbie) I want to learn about what is fun about it -or how it looks - or how hard/easy it is to fit a radio - or why someone likes it - I don't care about decalage angles and noses - that's what the Aerodynamics channel would be for

In the best of intentions,

Rich

 

[Konrad]

Personally I would like to see the following - so if there is a way to keep everyone happy:

1) A separate channel in this forum for Aerodynamics - anyone who wants to geek out on fluid dynamics and reynolds number can go there
2) If anyone (not picking on Konrad) want to ask a real question about a specific model, be it a critique, improvement, question etc: just do it via private DM - just to make sure we're not trying to show our chops in front of the studio audience (and I'm not necessarily saying Konrad does this, but by DMing someone directly, there is no doubt that the question is for real)- the reason I say this is that Doc seems to be one of the few (if not only) designers on this forum - so if you wanted to ask another designer, you'd have to email them vs post in this forum - so that should keep things fair-

Not trying to fan flames but just trying to appease all -
When I see a post title around REDShift etc, (as a newbie) I want to learn about what is fun about it -or how it looks - or how hard/easy it is to fit a radio - or why someone likes it - I don't care about decalage angles and noses - that's what the Aerodynamics channel would be for

In the best of intentions,

Rich

If the shoe fits name me.

Yes Doc, has been very easy to reach and I salute him for it. But nobody is going to agree with him (or me) 100% of the time. I think this thread was started just as a way to vent as I asked elsewhere many hard question based on my experience with his other products. I should have just let him vent.

There's the rub. How does one, in a meaningful way, describe why one like of doesn't like without going into detail?

Mutual admiration societies are of no use to me. That is why I going to detail in my threads as to why I like things or not. And more often than not as these are aircraft, it is based on the aerodynamics. It is hoped that looking at things in detail that all, myself included, can learn a thing or two.

 

[Doc J]

Personally I would like to see the following - so if there is a way to keep everyone happy:

1) A separate channel in this forum for Aerodynamics - anyone who wants to geek out on fluid dynamics and reynolds number can go there

Actually, Rich - I think that mght be a good idea.

2) If anyone (not picking on Konrad) want to ask a real question about a specific model, be it a critique, improvement, question etc: just do it via private DM - just to make sure we're not trying to show our chops in front of the studio audience (and I'm not necessarily saying Konrad does this, but by DMing someone directly, there is no doubt that the question is for real)- the reason I say this is that Doc seems to be one of the few (if not only) designers on this forum - so if you wanted to ask another designer, you'd have to email them vs post in this forum - so that should keep things fair-

I think this "model aerodynamics channel" is also a good idea.
Then perhaps for specifics about a particular model, its best keep it confined to DM.

When I see a post title around REDShift etc, (as a newbie) I want to learn about what is fun about it -or how it looks - or how hard/easy it is to fit a radio - or why someone likes it - I don't care about decalage angles and noses - that's what the Aerodynamics channel would be for

I like that idea a lot.

In the best of intentions,

Rich

Good stuff Rich!

Doc.