najary

Two in one - Canalizer and Air-Brake.

Here is the story how it was born:

We all looking for constant speed, I realized that the down lines are the only thing that we still have difficulty to control, we start it in a certain speed and the speed always increase, that is simply physics.

For years we are trying to solve this problem variously: Motor brakes, wide props, wide fuselage, thick airflows, round leading edges, contra rotation, air brakes, etc.

But we still haven't found a significant solution for that problem.

For some times I was thinking, why not we use a big Air-Brake like the F-15 Eagle has? And I started to think how it can be done in the fuselage floor.

In the meantime I saw the new CPLR GALACTIK with the anhedral ventral T canalizer and thought, wow!!! That is a good idea.

One day when I was asleep the idea came to me in my dream. Why not put the anhedral ventral T canalizer on a shaft rotate it and turn it to an Air-Brake, I waked up and as you probably understand I couldn't sleep for a quite a few hours.

In that time my friend Amram Leshed was judging at the W.C. I told him about my idea and asked him to consult the idea with some of the pilots.

Most of the pilots that he consulted with thought that it is not a good idea, only CPLR said why not try it and he asked Amram to tell him what will be the results.

CPLR responses gave me the last push to go ahead and build it.

Amarm and I went to the test flight.
http://www.youtube.com/watch?v=xyYGVDA7H20

I was really tense because we didn't know how the plane will behave so I reduced the Air-Brake gradually.

The Air-Brake required quite a few elevator down mix but it didn't have any pitch nor rolling motion.

The plane dived straight down very slowly in a constant speed!!!

The big surprise was when I flew the P-13 sequence, the rolling segments became much straighter, and I just couldn't believe that this is my plane!!!

One think is still a mystery for me: the ailerons became more sensitive so I had to reduce the movement; anyone has any thought way it could happen?

Best Regards,

Isaac Najary

Anthony-RCU

My Feedback: (2)

Very cool! Isaac you are always a great source of inspiration. Looking forward to more details so others can try this. Very curious to see the structure since I would imagine the loads could be high at such extreme deflections. Would have loved to see the elevator mix activated in the demonstration.

Maybe avoid spicy food before bedtime?

JAS

My Feedback: (2)

Very cool. I thought about a few different types of airbrakes (wing brakes like gliders, fuse brake like Hatta in 99...) but never thought to use a T. Maybe it begs the question, what if a top and bottom T were to rotate? Would they have to rotate 90 or would 45 degrees work? What effect would it have on the rudder? Awesome work as usual Isaac

Doug Cronkhite

My Feedback: (34)

Way to go!

As the saying goes in Golf.. You miss 100% of the putts you leave short. In airplane terms, you are guaranteed to learn nothing if you don't try. Trying new things is what led CPLR to the canalyzer in the 1st place.

I wonder how something like this would work. These are the speed brakes from a Fouga Magister jet.

apereira

Hello Issac,

Congratulations on a great idea, it looks you made it to work when CPLR removed the lower T, interesting.

On your ailerons being more sensitive, I think it could be due to the loss of stability in the horizontal stabilizer due to the disruption in the airflow, the stabs will resist the roll as well as the wings does, so by reducing the stab effectiveness the roll balance between the wing and stabs are reduced thus increasing the sensitivity of the ailerons, what do you think? If you deploy the brake in horizontal flight it might be kind of critical.

Regards

viper2003

T-brake was invented in 2012 by an spanish guy called Victoriano and used by spanish team in 2013 F3P world championship:

http://www.youtube.com/watch?v=phTXai-n4yc

regards

JAS

My Feedback: (2)

Doug, that's something like the wing brake I was thinking, but more along the spar. Not sure what it would do to the roll though

apereira

It might not work for F3A as it disrupts the airflow , but speed brakes are used in jets, and some cause a little roll when not adjusted properly or during extension/retraction.

apereira

Very impressive!

Doug Cronkhite

My Feedback: (34)

If they were symmetric top and bottom it could work, but I think you'd have to be really careful on rigging.

amram

I find Doug point very true and basically that was also CPLR response. CPLR told me in SA: "Try this. in my experience strange ideas that were considered to be nonsense found to be real value for F3A quality and ideas with 100% potential to be real value for F3A quality found in test to be failure". I think this reaction gave Isaac the final push to build it. For example all estimates and calculations done by really educated people showed that model will pitch down when break will apply. for me (stupid guy) it was just clear that it will pitch up and it ended up to be this way... so some time it is just better to forget all and just go and try.
I must also admit that I was very skeptic about this and I was very surprise to see the result in the air.
Also, need to metion that in order to get very good break on Najary' current model as well as quality speed control, only ~40 degree deflection is needed.
finally, Najary' did another smart thing and that was he assigned additional trim lever to be able to trim (like other control surfaces) the basic (straight and level) angle of the canalize. That is MAYBE why he came to know and was able to fine tune the advantage of these canalizes for a straight and level flight!!!

Good Job Izik!. You are a great value to F3A World community...

Amram

najary

Here is how it was build:

Best regards,

Isaac Najary

najary

The structure that remains in the fuselage if you want to remove the system weighs 29 gram.

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Alex Voicu

Great piece of engineering Isaac! Thanks for sharing.

macleote

Hi,
any video in flight ?

++
seb

Dansy

My Feedback: (53)

Wow great thinking...looking forward to see it in flight! Well Done

n233w

Cool.

My guess about the aileron sensitivity is that you've got higher pressure air spilling off the tips of the brake spilling onto the underside of the ailerons, which could possibly make them more responsive.

Bill

najary

Here are some more details:

The anhedral ventral T canalizer is in the same angle as the top canalizer: -1.0 degrees (the wind in +0.8 degrees), so it have the same affect as you add a big canalizer to a plane that does not have any canalizer, but in this case it almost double the affect, the rolling segments became much straighter, I just couldn't believe that this is my plane!!!

As for the air-bake, the angel is about 50 degrees so the airflow after the air-bake goes under the tail so it does not affect the elevators or the rudder.

The air-brake required quite a few elevator down mix but it didn't have any pitch nor rolling motion.
The plane dived straight down very slowly in a constant speed!!!

When you apply the air-brake in horizontal flight you don't have any pitch or rolling movements.

Best regards,

Isaac Najary

wryman

My Feedback: (9)

I would like to see a video of downline with and without the brakes to see the difference

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najary

Weight before finishing

najary

Apply 16 gram /square meter micro glass under vacuum pressure.

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