0
   

Number 85 - To see a tree asmiling.

 
 
danon5
 
  3  
Reply Mon 12 Apr, 2010 07:43 am
@danon5,
Probably an easier way to describe an aircrafts "vortex" is imagine the wing of the aircraft passing through a bunch of pingpong balls. The wing is shaped sort of flatter on the bottom and more rounded on top (usually). As the wing passes through the balls - the balls on the bottom sort of flow in a straight line. The ones on top are forced to curve up and over the top of the wing - thus traveling a longer distance (and Faster) in order to meet with the same set of balls that they were with when split by the leading edge of the wing. The faster speed of the balls on the top of the wing create a lower air pressure while the slower balls traveling in a straighter line on the bottom of the wing create a higher pressure. That is (Lift) and is what makes the aircraft want to go (Up). NOW, the balls pass over and under the wing all across the surface of the wing at a fairly steady rate UNTIL they reach the wing tip. At that point the resulting Downward angle of the balls stop their downward plunge and as a result at the tip of the wing the balls are pushed INWARD towards the fuselage of the aircraft. The balls then meet with the downward forced balls and thus they are forced into a spiraling motion with the topmost balls spinning inward towards the body of the aircraft. The spinning air from the tips of the wings are like tiny tornados and as a result create Drag that actually acts to slow down the aircraft. This spinning air effect is VORTEX.
Now, when a helicopter is hovering the roters (which are the WINGS of the aircraft) are going in a circle and the vortex is shaped like a donut with the body of the aircraft hanging in the donut hole. As the helicopter begins to move - the donut hole drags back because the pingpong balls in front of the movement of the aircraft are being PUSHED out of the way of the balls forming the DONUT. At a certain airspeed, the helicopter enters the forward edge of the donut and proceeds THRU the downward traveling balls and then begins the tiny twin tornado effect described above and the result is a normal vortex just like any other aircraft. The moment the helicopter enters the forward vortex and passes through it is called TRANSLATIONAL lift. In effect the helicopter is escaping the center of the donut hole and is now in front - the "donut" vortex no longer is there - the vortex translates into a normal version. During the translation the entire helicopter shakes and vibrates.
Now you all know what makes planes and helicopters fly!!!!!!! It's that simple.

The Osprey has double roters which complicates the vortex effect of a normal helicopter. The developers had a hard time overcoming this when the Osprey was newly developed. Mostly, from my understanding, the controls of the Osprey are computer controlled. It must be really interesting to fly.


0 Replies
 
High Seas
 
  2  
Reply Mon 12 Apr, 2010 10:04 am
@danon5,
danon5 wrote:

Hi Hi --

Thanks for the article - I enjoyed it a lot. I don't know if you know, but, I am a pilot in not only the "fixed wing" aircraft, but, am a pilot in the helicopter. .
....


Hey, I never knew that! Only flown fixed-wing (props) myself, know helicopters are much more complex.

The Osprey in particular is horrendously complicated, much more so that the Harriers, which also have tilting propellers, but are otherwise regular airplanes. I hope the Osprey's computerized controls work well in battlefield conditions, always wonder about lack of manual backups in aircraft of all kinds!
0 Replies
 
ehBeth
 
  2  
Reply Mon 12 Apr, 2010 12:08 pm
@danon5,
Clicked in the a.m. (and on the weekend).

The concert was wonderful. The slide-show (do they still call them that?) really added to the experience. Mountains/birds/garbage dumps/white water rapids/frogs and toads/Arctic wolves. They had it all.
danon5
 
  3  
Reply Mon 12 Apr, 2010 01:06 pm
@ehBeth,
ehBeth, I'm sooo happy for you. Glad the concert went ok. Sounded like it would be terrific. A real moving event.

Hoft, If you have flown a fixed wing plane you can fly a helicopter. They both perform the same in flight. It is the hovering of the helicopter that takes all five of the pilots control elements - 2 arms, 2 legs and 1 pucker factor that you normally just sit on. Anyway, after a short time of practice you could hover, go through Translational Lift and fly a helicopter. No problem.

Once, a long, long time ago - I was at Ft Rucker, AL going through helicopter transition. I was already a fixed wing pilot in the US Army and had a couple thousand hours at the time. The instructor pilot with me took us out on the first day to a HUGE open field with no obstructions ANYWHERE. There was a good reason for that. The very first control system I experienced was the Pucker Factor as the helicopter slowed down to land. I thought it was going to STALL and we would crash and burn. As you know, in a fixed wing aircraft you don't slow down at altitude!!!! Anyway, the big open space soon came in handy as I first started to learn how to HOVER the helicopter at 3 ft above ground. At that point I soon learned that ALL FIVE control factors HAD to be in play constantly. It didn't take long and I had the hover/pucker factor conquered. After that flying the bird was fun - except when I looked UP and BACK through the "Green House" (that's what we called the green plexiglass directly over the pilots head). As I looked at that I became a little nervous because I could see ALL THOSE different parts ALL GOING in different directions ALL AT ONCE!!! The best thing about a helicopter is the "Jesus Nut"!!!!!!!!!!! That's the only thing keeping the rotor blades fixed to the helicopter - ONE single nut!!!!! I like it when that stays on.
One fine day toward the end of my training and after I had gotten to know my instructor pilot a little better - I began to ask him questions, "What would happen if (this or that) broke on the helicopter?" then several more questions which he answered dutifully. At last, I asked him what would happen if ALL of the other problems happened at the SAME time!! He pushed his chair back a little leaned back and with a smile said, "Well, Sir, then you reach over with your right hand unbuckle your seat belt, then climb up and sit on the stick and let the Safety Board try to figure it out."" I bought him a beer at the club later. That was a good one.

teenyboone
 
  2  
Reply Tue 13 Apr, 2010 07:15 am
Today is Tuesday! Clicked on Monday and forgot to post it! All clicked for today too! In the 50's today. Enjoyed the Spring while it lasted!
0 Replies
 
alex240101
 
  2  
Reply Tue 13 Apr, 2010 07:37 am
@danon5,
Great story danon5. I would like to see all the mechanical movement in the greenhouse. On film would be preferred.

Clicked.
danon5
 
  2  
Reply Tue 13 Apr, 2010 08:16 am
@alex240101,
Hi teeny - Great clicking, you have just made another tree smile.

alex, The "greenhouse" is a plexiglass window above the pilots head in the UH-1 (HUEY) helicopter the US Army uses. Looking through the greenhouse you see the rotor and all it's control arms going around and around in a small circle. That's what I was talking about. Before each flight the pilot of a helicopter goes over all the connections of the parts of the aircraft. Each part is bolted on and then secured with a "cotter pin". If one of the pins is missing it could easily cause the bolt to become loose and could just as easily cause the aircraft to become a rock instead of an airplane. There are a heck of a lot of pins holding the nuts onto the bolts that hold the parts on the plane. Each one is checked by the smart pilots before each flight. Especially the "Jesus Nut" --- It's real name is Rotor Retaining Nut - and it's big and strong. The pilots in the Army called it the Jesus Nut because IF it ever came off you would be saying "Jesus Christ" followed probably by "Oh S--t" in very high octaves. My last flight in a helicopter was after the end of the Vietnam conflict during the late 1970's --- so, I don't have a way to show you a picture. Sorry.
0 Replies
 
High Seas
 
  2  
Reply Tue 13 Apr, 2010 01:34 pm
@danon5,
danon5 wrote:


Hoft, If you have flown a fixed wing plane you can fly a helicopter. ...


It's not I would doubt your word, but even the most worldly among us can, and will, suddenly find religion if they discover that the "wings" of their aircraft are secured to said aircraft by a single screw - can see exactly how "Jesus nut" was called that to begin with!

I went to McArthur airport in Long Island couple of days ago with a friend (owner of twin-engine turboprop) and we had a grand time - also flew over where the poor baby whale was beached and had just died and tipped our wings a few times as a sign of respect. I posted links on Ms Olga's thread on whales. Lots of other small planes did something similar (the tiny Hamptons airport was annoyed with us, but around midnight they don't have a whole lot of small-plane traffic, though they of course track commercial and military flights en route, and anyway their controllers love dolphins and whales too!)

Danon - all the best to you and Patti, and thank you: this has been such a fun thread; I was glad to see seldom-appearing fellow clickers (I do click away, most days) and appreciated your ping-pong ball explanation of helicopter aerodynamics; but, to tell you the absolute truth, after I read it very carefully and before my friend and I took his plane out of the hangar at McArthur, I went around and counted rivets, nuts, screws, bolts, and suchlike paraphernalia connecting wings to frame. I was reassured upon reaching 2 dozen, with more to go. No offense meant Smile
High Seas
 
  3  
Reply Tue 13 Apr, 2010 01:45 pm
@ehBeth,
ehBeth wrote:

The concert was wonderful. The slide-show (do they still call them that?) really added to the experience. Mountains/birds/garbage dumps/white water rapids/frogs and toads/Arctic wolves. They had it all.

Sounds fascinating, except for the.... garbage dumps? Wonder what musical piece could have been played with that one - for years btw when I lived in Boston the New England Aquarium (just across from my then apartment's terraces) would play the complete Handel Wassermusik along with the most wonderful light show. They used to keep seals in an outdoor pool at the time, but then had to put up transparent walls around the pool because some criminals (there's no other word) fed stuff like bottle-tops to the seals which naturally got very sick as a result. Thanks, ehBeth!
danon5
 
  5  
Reply Tue 13 Apr, 2010 07:34 pm
@High Seas,
Hoft, Good wishes and good luck to you and your's.

Happy flights.

Dan

Stradee
 
  4  
Reply Wed 14 Apr, 2010 02:07 pm
@danon5,
wow, i leave for a few days and when returning, find the most interesting postings!

Hoft, had no idea the Osprey was such a challenge to fly.

Here's a pic and specs of the Ospery V 22... (for those who arn't certain what the plane looks like and flying capabilities.



http://cdn.globalaircraft.org/media/img/planes/lowres/v-22_4.jpg

Primary Function: Amphibious assault transport of troops, equipment and supplies from assault ships and land bases
Contractor: Boeing Defense and Space Group, Philadelphia, PA; Bell Helicopter Textron, Ft Worth, TX; Allison Engine Company, Indianapolis, IN
Crew: N/A
Unit Cost: $40.1M (Total Program Recurring Flyaway, Constant Year, FY94$)
Powerplant
Two Allison T406-AD-400 turboshafts each rated at 6,150 shp (4586 kW) take-off and 5,890 shp (4392 kw) continuous running.
Dimensions
Length: 57' 4 inches - Spread
63 feet 0 inches - Folded
Width: 84' 7 inches - Spread
18 feet 5 inches - Folded
Height: 22 feet 1 inches - Spread
18 feet 1 inches - Folded
Weights
Empty: 31,886 lb (14463 kg) -- equipped
Maximum Takeoff: 60,000 lb (27442 kg) -- for STO
Performance
Speed: 316 mph (509 km/h / 275 kt) -- airplane mode
115 mph (185 km/h / 100 kt) -- helicopter mode
Ceiling: 26,000 feet (7925 m)
Range: 200nm Pre-Assault Raid with 18 troops
200nm Land Assault with 24 troops
Armament

Godspeed ~

Beth, glad you had a great time at the concert. Might want to check out the series "Life" airing on the Discovery Channel. Beautiful photography and sound track.

Hi ya Teeny, Alex, and dan.

Learned so much reading your postings also, dan. Thanks!


http://rainforest.care2.com/i?p=583091674
danon5
 
  3  
Reply Wed 14 Apr, 2010 03:04 pm
@Stradee,
Hi Stradee, glad you're back and safe. Looks like some cold weather went your way. Hope you didn't get too much snow........ It is Springtime you know....... Grin. Good clicking me heartie !!!! ((That's my takeoff of Flynn in a pirate suit.)) Or, Captain Long John Silver!!!! I have visited the Pirates House in Savannah, GA many times -- that is purported to be the house where Long John Silver stayed........ You can Google it if you want. It's a fun place to see.

All clicked this day and I see a tree asmiling..................

ehBeth
 
  3  
Reply Wed 14 Apr, 2010 04:14 pm
@High Seas,
High Seas wrote:
Sounds fascinating, except for the.... garbage dumps? Wonder what musical piece could have been played with that one


my puter is having some kind of [email protected] with opening pdf's tonight

http://www.tafelmusik.org/concerts/programme_notes.htm

the third link in this grouping

April 7 - 11, 2010

Forces of Nature Programme Listing
Forces of Nature Programme Notes
Photography in the Forces of Nature Concert

has info about the photographs used with each piece of music. The garbage dump pix were in the final poriton of the show (if anyone can open it) after the intermission

Telemann's Alster piece - with the frogs and crows arguing - got a lot of grins and chuckles - one of my favourite pieces of programmatic composition
Thomas
 
  2  
Reply Wed 14 Apr, 2010 06:25 pm
@ehBeth,
ehBeth wrote:
Telemann's Alster piece - with the frogs and crows arguing - got a lot of grins and chuckles - one of my favourite pieces of programmatic composition

Hmmm. Your family must be from Hamburg or something.
ehBeth
 
  2  
Reply Wed 14 Apr, 2010 07:42 pm
@Thomas,
Ho ho Ho - you are one funny fella Mr. Green


are you suggesting I'm biased?
are you suggesting that isn't a fun piece of music?
hunh!
danon5
 
  2  
Reply Thu 15 Apr, 2010 08:09 am
@ehBeth,
ehBeth, thank you for the link.......... Great works. So, Haydn was close to the Esterházy's.. I have visited The Esterházy Palace in Vienna and have to say it is absolutely beautiful.

Although, I must say that nearby the palace is The Esterházy Keller built underground in what was originally the south moat of the Roman outpost which actually began the city of Vienna. They called the outpost Vindibona (sp). WOW, it's lively during the early evening hours. I never had the courage to stay too late at night.

Thanks again for the link.

And, for saving another tree asmiling.

0 Replies
 
ehBeth
 
  3  
Reply Thu 15 Apr, 2010 10:43 am
@ehBeth,
Sorry - I misfired - the information about the photographers is in the third link, not the actual photographs.

from the second link

Quote:
Jan Dismas Zelenka was Czech but spent the majority of his career as a musician working in Dresden. He was originally hired as a violone player in the court orchestra and eventually became a composer as well. Most of his compositional output was sacred vocal music, but he also wrote six trio sonatas which are characteristically original, with quirky rhythms and
chromaticism, and display his mastery of counterpoint.

The contrapuntal quality of the music inspired me to choose it to represent the urban environment " in this highly complex writing each part is independent of the others, and yet when intertwined, complement each other to create a complete machine-like structure.
Stradee
 
  2  
Reply Thu 15 Apr, 2010 11:14 am
@danon5,
Road trip to daughters, shopping...(fabulous dinner) and the plus of leaving mountain weather for warmer temps was such a good change.

Today though Spring is here again, mild temps, and much gardening to attend to. Much work reprieve over for 10 days then new trek to the city.

Ah...the Silver... According to Stevenson's letters, the idea for the character of Long John Silver was inspired by his real-life friend William Henley, a writer and editor.[3] Stevenson's stepson, Lloyd Osbourne, described Henley as "..a great, glowing, massive-shouldered fellow with a big red beard and a crutch [Henley was crippled]; jovial, astoundingly clever, and with a laugh that rolled like music; he had an unimaginable fire and vitality; he swept one off one's feet". In a letter to Henley after the publication of Treasure Island Stevenson wrote "I will now make a confession. It was the sight of your maimed strength and masterfulness that begot Long John Silver...the idea of the maimed man, ruling and dreaded by the sound [voice alone], was entirely taken from you".

What i want to know is if Fleur Da Silva survived Silvers last escapades and "retirement".

Pirates, me matey...pirates.



0 Replies
 
danon5
 
  1  
Reply Thu 15 Apr, 2010 11:14 am
@ehBeth,
Beth, don't worry about msifiring (((Hi, Iz!!!))) I do it all the time. Your posts have made me think of another musical group that is soooo good and I just love and we play their music each Christmas!!! Mannheim Steamrollers = http://s0.ilike.com/play#Mannheim+Steamroller:Carol+of+the+Bells:143527:s18275.2428.9064050.1.2.36%2Cstd_66b2041e8dd2454aaf25134b4d5a8620
Sample song = 'Carol of the Bells'
They all use period instruments and play it the way they feel it should sound - to them of course and to me and to millions.

Love all old stuff - especially Mozart. He, to me, is eternal.

Good stuff...............!

danon5
 
  2  
Reply Thu 15 Apr, 2010 11:19 am
@danon5,
Whoa!!! Hey, Stradee, glad to see ya. (Sarah Palin improv)
We posted at the very same minute and ya beat me toit by a Shot!!! (More Tea stuff)
Big Grin........

 

Related Topics

 
Copyright © 2022 MadLab, LLC :: Terms of Service :: Privacy Policy :: Page generated in 0.04 seconds on 01/18/2022 at 01:14:36