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Number 85 - To see a tree asmiling.

 
 
sumac
 
  3  
Reply Wed 7 Apr, 2010 10:06 am
Clicking and reading, reading and clicking. Heading up to near 90 degrees again today.
Stradee
 
  2  
Reply Wed 7 Apr, 2010 06:26 pm
@sumac,
Spring has sprung!

Light winds, warm temps, dark blue sky....wuhuuuu

Tomorrow the great outdoors



http://rainforest.care2.com/i?p=583091674
danon5
 
  1  
Reply Wed 7 Apr, 2010 06:30 pm
@Stradee,
Great clicking everyone ------

sumac, the cold front that just went through NE TX is heading your way. That should cool you a little.

ehBeth, Sock Hops with shoes !!!!!!!

alex240101
 
  3  
Reply Thu 8 Apr, 2010 05:40 am
@danon5,
Good morning danon5, Stradee, sumac, teenyboone, ehBeth, and others.

"you have saved 2,024.4 sq. ft. so far so far"

On a roll.
danon5
 
  2  
Reply Thu 8 Apr, 2010 11:21 am
@alex240101,
alex, thanks guy............ I do like it when you post. Otherwise, I'm dominated by all these females!!!! OH!!!!!!! Wait, that's a good thing........... Big Grin

(((I don't know who you are so I'm hoping your name isn't Alexandria -- makes no difference to me.)))

I'm just a bag of wind. And, I'm old and I'm not well.

Joking.

All the well wishes in the world to you Wildclickers --- Keep those trees asmiling!!!!

ehBeth, a little more trivia =====
You mentioned something about 'keep on clicking'? That expression of thought came directly from the 1950's.............. At that time there were all sorts of scary things in space around our little blue ball. AND, since it was directly after WWII and all the technical advancements that happened then --- we were in a tech period............. "PUSH BUTTONS" were such a rage that we - and the scientists thought and projected that in the future human beings would have only ONE digit on their hands. That's true.

That's my earliest rememberance of the term.

AND, WE WILDCLICKERS HAVE BEEN CLICKING FOR ?? ((ehBeth, when did we begin?")) MANY YEARS!!!!!!!

PS: The scientists must have mistakenly thought that we humans would have been clicking with only one finger to make that genetic judgement. Probably they were thinking of the "middle" finger!!!!!!! LOL

Stradee
 
  2  
Reply Thu 8 Apr, 2010 03:05 pm
@danon5,
When i read "keep on clickin'"...i'm reminded of the following famous logo...

http://www.seeklogo.com/images/K/Keep_On_Truckin-logo-CE805929F6-seeklogo.com.gif

It was published in the first issue of Zap Comix in 1968. A visual riff on the lyrics of the Blind Boy Fuller song "Truckin' My Blues Away", it consists of a procession of four smiling men, drawn in the artists distinctive style, strutting confidently across various landscapes. The strip's drawings became iconic images of optimism during the hippie era. Like most underground comics "Keep on Truckin'" was not copyrighted, and images of it have been widely reproduced on T-shirts, posters, and other items.

Just a bit of trivia from this long ago Hippiefied person. Very Happy

And yep, still have memorabilia from the day.



0 Replies
 
teenyboone
 
  3  
Reply Thu 8 Apr, 2010 05:00 pm
@danon5,
Danon,
It was 93 yesterday, 87 today and all weekend it was drop dead gorgeous weather. Wish I knew how to post photos, I could show you, but I'm just glad
to be here! All clicked, too!
ehBeth
 
  3  
Reply Thu 8 Apr, 2010 05:05 pm
@danon5,
clicked in the morning

marvelled at the thunder storms in the afternoon

yawning in the early evening

(will have to check as to when we started clicking - I think it was the first year care2 was around - 1999 I think - we are part of the original crew)
0 Replies
 
danon5
 
  2  
Reply Thu 8 Apr, 2010 05:46 pm
@teenyboone,
Teenyboone---
I do have to admit to you that I've had your recipe for gumbo for many years and I still have it. You are one angel when it comes to food......
I love it.

Stick around and join us in celebrating another tree asmiling!!!!!!!!

PS: How is your sister? I do understand she left the Pass Christian area before the hurricane...........?

Happy Easter to all Wildclickers even thou I don't have any children around here looking for ((EGGS))???? And, they are all HARD BOILED and PAINTED??? GEEEEESSSSSSEEEEE.........

Oh, Yeah...... I do have a son at Fort Walton Beach, FL!!!!!!!

Oh, Yeah....... and, an X wife....... But I still admire and love her and my son and we do talk to each other.

It's nice to remain friends. And, family.

She is such a special person - as is our son, Wade.

Thanks for clicking all you Wildclickers!!!!!!!!!!



alex240101
 
  3  
Reply Fri 9 Apr, 2010 05:22 am
@danon5,
Good day danon5. Clicked.

Be careful, you may be wearing a wig soon.

Water level is up a couple feet, from this weeks rain. Many quackers, quacking joyously.
0 Replies
 
teenyboone
 
  2  
Reply Fri 9 Apr, 2010 05:58 am
@danon5,
I am honored that you have it. When it's COLD outside it's the perfect dish, with
crusty French or Italian bread, cut and buttered!

It's 54 in rainy Asbury Park, right now. It won't be as warm as yesterday, but tolerable in the high 60's to low 70's depending on which part of the State you live in. Crazy NJ! If you live in the North, you're either a Jets/Giants,
Mets/Yankee Fan. If you live in South Jersey, you're apt to follow the
Phillies/Eagles! With only 2 TV stations, NJN and News 12 NJ, you're stuck
with New York. If you have Cable, like I do, you get all of the Philadelphia
Stations too!

Poor New Jersey, a State with NO identity! WRONG! New Jerseyans are
predominantly Democrat and Liberal; a so-called "blue" State, so why was a Catholic Republican elected? I had nothing to do with it, but you get what you elected, I always say. He's turning out to be the pro-Bush wonk he always was/is! Anti-environment, anti-education and everything the "wild-clickers" advocate the most. You can't be pro anything, if you aren't educated. I see a "mass" exodus of seniors and laid off educators, unless he's
recalled! Sorry for the politics.
0 Replies
 
teenyboone
 
  2  
Reply Fri 9 Apr, 2010 06:08 am
@danon5,
Whoops!
My sister moved to North Jersey with her daughter in 2004, exactly 1 year
before Katrina, 8/29/04, which IS my birthday, also. HBO is airing a series
called "Treme", one of the oldest neighborhoods of color, in the City.

That area is where Blacks congregate for Mardi Gras, which was tree-lined with beautiful old oak trees, which were destroyed, when I-10, was constructed in the mid-60's. It was also an attempt to take away a historical gathering area for Creoles, but under the overpass, that came straight through the area, gave the area a waterproof shelter! I was there on Mardi Gras Day, this year.

Oh God, I'm talking about Race! I hate it when I do that! I moved to New Jersey to get away from that, and ran head long into it, here! Sorry, about that.
Stradee
 
  2  
Reply Fri 9 Apr, 2010 04:15 pm
@teenyboone,
So good seeing the widlclickers posting today!

Well, we've got sunshine for one more day, then rain and snow.

Warm clothes at the ready (today, Springy togs)

Visiting my daughter next week, looking so forward to seeing her.

Know what ya mean, dan. Keeping kids close and loving them always...

Teeny, not to worry. The thread talks politics, race, all kinds of stuff. Hearing from you is what counts.

Beth, Alex, sue, and all the wildclickers, have a fab evening.



danon5
 
  2  
Reply Fri 9 Apr, 2010 05:25 pm
@Stradee,
Yes, Stradee, WX is fine here also. sumac is getting the promised cooling.

Good clicking to all clickers - both posters and nonposters - thanks.

teeny, we're in the race together - that's what I think.

0 Replies
 
ehBeth
 
  3  
Reply Fri 9 Apr, 2010 06:55 pm
@Stradee,
Snow flurries on my way home tonight. Big big big flakes falling down from the skies tonight. Crazy temperature, weather variations going on.

Going to a 'green'-themed concert tomorrow night. Looking forward to it.
ehBeth
 
  3  
Reply Fri 9 Apr, 2010 07:21 pm
@ehBeth,
from a review of the concert

Quote:
Tafelmusik Baroque Orchestra is bridging the calendar gap between Earth Hour and Earth Day this week with its own green-themed program that celebrates our flora, fauna and environment in music and images.

This is no ordinary concert. The period-instrument orchestra stands on an artfully lit stage, playing a 17th and 18th century pot pourri as pictures pass by on a large, circular screen.

There’s no applause between the pieces, nor is there enough light in the church to read the program notes. One has to sit back in happy surrender to the passing audio-visual spectacle, conceived by Tafelmusik violinist Julia Wedman and designed by Raha Javanfar and Glenn Davison.

The first performance on Wednesday night revealed a slick show, alternating musical virtuosity with shorter, moody moments " many inspired by nature, such a bird song, frogs and a passing storm.

Nearly every section and member of this multi-talented orchestra gets to shine. And there are several instances of ear-popping surprise, such as in the “Ebb and Flow” section from Georg Philipp Telemann’s Wassermusik, where the double-reeds and horns have a grand old time weaving together dissonances and complex rhythms.

We would have a moment of reflection as a single, low spotlight alighted on Christina Mahler performing the Sarabande from J.S. Bach’s Suite No. 2 for solo cello.

Wedman herself delivered a particularly sparkling virtuoso solo turn in Antonio Vivaldi’s Concerto for Violin No. 8, better known as the “Storm at Sea.”

Green has rarely sounded so golden.



definitely something to look forward to!
danon5
 
  2  
Reply Sat 10 Apr, 2010 07:57 pm
@ehBeth,
That sounds wonderful ehBeth. Great Big Flakes? Where's Spring?? Your review brought to mind a concert I attended in Vienna. It was 1980 and the conductor was the first American to be so honored. Maazel I believe. It was the New Years Day Concert at the Musicverein (sp). The American did a wonderful job and stayed in Vienna for several years - earning himself a very naughty reputation.

Good clicking all.

Stradee
 
  2  
Reply Sun 11 Apr, 2010 09:43 am
@ehBeth,
g'day wildclickers

Quiet Sunday....storm's gearing up for snow, rain, and wind.

Lovely concert, Beth. Enjoy

0 Replies
 
High Seas
 
  2  
Reply Sun 11 Apr, 2010 01:32 pm
@danon5,
Danon - couldn't help noticing you've been dropping polite hints for someone to pick up from you the wildclicking baton (so to speak) and start a new thread; I'd volunteer but mostly am overseas these days and not posting, and I know it's hard work for the original author.

I do, however, have a small present for you, with something you may not have known concerning aircraft - I hadn't even heard of it, which doesn't mean much, of course! - and apologize for the length of the article but it's not available online yet. It's on a condition called "vortex ring state", and I know at least Danon will want to read it all, and hope it will also be of interest to others:

Quote:


--------------------------------------------------------------------------------


Adapted from 'The Dream Machine:? The Untold History of the Notorious V-22 Osprey'
RTRWN00020100402e64f00005
4029 Words
15 April 2010
Rotor & Wing
Vol. 44; Issue 4
English
Copyright © 2010 PBI Media, LLC. All rights reserved.
Rotor & Wing contributing editor Richard Whittle has written a history of the V-22 Osprey. The book, which Simon & Schuster will release on April 27, can be ordered now on Amazon.com. Rick agreed to share an excerpt in advance with R&W readers.

By Richard Whittle

The dream turned into a nightmare the evening of April 8, 2000, at a dusty desert airfield near the southeastern Arizona town of Marana. The Marine and Air Force pilots and maintainers of the Multiservice Operational Test Team, the MOTT, had begun the Osprey's most important stage of testing yet, Operational Evaluation, five months earlier. The results of OPEVAL would determine whether the Osprey could go into Full Rate Production, so the aviation branch at Headquarters Marine Corps was paying close attention. The Marine Corps' Deputy Commandant for Aviation, Lieutenant General Fred McCorkle, had visited Paxtuxent River Naval Air Station on Nov. 3, 1999, to kick the tests off. On April 8, the MOTT's four Ospreys--two carrying Marine infantry in the back--took off from Yuma, Arizona, for an exercise called a "Noncombatant Evacuation Operation," simulating the rescue of civilians from an embassy. Marines would play the role of evacuees; Marana Northwest Regional Airport, 25 miles northwest of Tucson, would play the embassy.

The MOTT had done similar missions before. But this time, after the first two aircraft approached the airfield and tilted their rotors upward to land, the second Osprey snapped into a right roll and plowed into the ground with its belly up. It exploded in a fireball that lit the evening sky for miles. The pilots, Major John A. "Boot" Brow and Major Brooks S. "Chucky" Gruber, as well as two enlisted crew chiefs and fifteen infantry riding in the back of their Osprey, were killed instantly. The first Osprey, piloted by Major James M. "Lefty" Wright and Major Anthony J. "Buddy" Bianca, was nearly lost as well. Wright, Bianca, three enlisted crew chiefs and eighteen Marine infantry in the back of their Osprey survived a hard landing that left them shaken.

Three days after the crash, McCorkle came to the Pentagon press briefing room to give the media the first of what he promised would be regular updates as the investigation into what had happened at Marana progressed. "Right now we have no indication of what caused the accident," McCorkle said. "I've heard on a number of news (reports) that we were looking at pilot error. We are not. We're looking at anything that caused the accident, whether it's material, whether it's mechanical, or whether it was human factors-related. And right now we have none of that information." McCorkle stiffened a touch when a reporter asked if he'd heard that the parents of some of the infantry killed were saying the Marines had used their sons as "guinea pigs" in a test aircraft, a machine that "was unsafe and their child had communicated that to them." The Ospreys at Marana were "in no way test aircraft," McCorkle said, they were production models the Marines would be flying in operational squadrons for years to come. He had flown the Osprey himself, and his confidence in it was unshaken. "I consider this to be the best aircraft that I've ever been in. This accident, to me, is not going to do anything to our MV-22 program," McCorkle said. No Ospreys, including the prototypes assigned to developmental test pilots at Pax River, would fly for now, but McCorkle was sure they would soon. "There's no doubt in my mind whatsoever, you know, that the full rate of production decision will be made with Milestone III and that it will go through."

McCorkle was in a good mood when he returned to the Pentagon press briefing room next, on May 9. He was there to confirm, as CNN had reported five days earlier, that the crash investigators had found nothing wrong with the Osprey. Using charts on an easel, McCorkle described how the accident had unfolded. He didn't name any of the pilots, but he explained that those flying the first Osprey into Marana, Wright and Bianca, had missed their 3,000-foot checkpoint and begun their approach into the airfield late. Rather than wave off and go around, they had come down "high and hot," forcing Brow and Gruber to follow in what none of the pilots seemed to sense was a pell mell descent. McCorkle's third chart traced Brow's speed and altitude over the last seconds of the flight, as reconstructed from his Osprey's Crash Survivable Memory Unit, a device that records airspeed, altitude, and other data. "In summary, the data shows that the mishap aircraft was in a high rate of descent at a relatively low forward airspeed," McCorkle said. "These characteristics can lead to a condition known as power settling, or vortex ring state."

Here Be Dragons

With that, McCorkle introduced a new, and for many people occult-sounding term into the debate over the Osprey. "Vortex ring state" was esoteric not only to the general public but in the aviation world as well. It was a term from fluid mechanics, an expression even an aeronautical engineer could go a career without hearing very often. Vortex ring state described a condition a rotor could get into as a result of what Navy and Marine Corps pilots called "power settling" and Army and Air Force pilots knew as "settling with power." What it all amounted to was a way to describe a rotor that was no longer creating thrust and lifting as it should because it was descending into its own downwash too quickly.

An MV-22B Osprey lands outside the city of Marjah, Afghanistan in February. Photo by Lance Cpl. Justin Loya

A rotor creates thrust both by pushing air downward and by pulling air through the "rotor disk," the circle a rotor's blades describe as they rotate. At the tips of the blades, some downwash circles back over top of the rotor disk and is pulled back through. This disturbed air interferes with a rotor's ability to create thrust only minimally--unless the rotor descends into its own downwash at the same velocity the downwash is moving. In that case, most or all of the downwash recirculates through the rotor disk rather than racing downward faster than the rotor and creating thrust. The downwash is now churning in a "vortex ring," an air flow pattern seen in smoke rings, and the rotor has entered "vortex ring state." When a rotor goes into vortex ring state, it no longer creates the thrust it should, and the aircraft begins to descend faster than the pilot wants.

When an aircraft descends too quickly, a pilot's natural tendency is to add power to arrest the descent, but in vortex ring state, adding power produces the opposite of the desired effect. In a rotorcraft, adding power also adds pitch to the rotor blades, increasing the angle at which they hit the air. Adding power and pitch to a rotor in vortex ring state only creates more disturbed air and pulls it back through the rotor disk faster. Instead of flowing as it should and creating thrust, the air begins bouncing in and around the rotor disk chaotically and the aircraft loses lift even faster. Helicopter pilots are taught about the hazard and told that the best way to get out of it is to reduce power to slow the rotor while flying into "clean air" by tilting their helicopter's nose forward. That tilts the rotor forward and increases forward airspeed. Without sufficient altitude, though, there may be too little time to do that, so pilots are urged simply to steer well clear of vortex ring state by never descending too quickly at slow speeds. It's the rotary wing aviation equivalent of an ancient cartographer writing on a map "Here Be Dragons." Helicopter pilots learn the rule and avoid that edge of the flight envelope out of habit. They simply don't go there.

$50 Million and Time

The combined rate of descent and speed at which any particular rotorcraft might go into vortex ring state depends on various factors--the size and shape of its rotors, its flying weight, wind conditions, etc. The rule of thumb for most helicopters, though, is to avoid descending faster than 800 feet per minute when flying forward at 40 knots or less. Where the actual line existed for the Osprey was something the program's developmental test pilots hadn't determined. Hundreds of test flights to explore that part of the Osprey's envelope had been planned. Nolan Schmidt, the program manager and a Marine Corps colonel at the time, told me years later that those tests were scrapped in 1998 to save time and money. The Navy Department was going to cut the Osprey program's budget for the coming fiscal year by $100 million, Schmidt said. After consulting with the Boeing engineer in charge of flight testing, Philip Dunford, Schmidt said, the program managers decided they could save about $50 million and a lot of time if they didn't do all the tests planned for the Osprey at high rates of descent. A few tests already done had indicated that the Osprey could safely descend at 1,200 feet per minute below 40 knots airspeed anyway, so Navair and company managers decided to simply adopt the standard rule for helicopters. It was enough to know there were dragons lurking beyond a descent rate of 800 feet per minute at 40 knots or less, so why test? "There was no practical need for any rotorcraft that we knew of to have to exceed that boundary anyway," one of the Osprey's developmental test pilots in those days told me. The flight clearance placard setting the limits on how the MOTT could fly the Osprey simply adopted the standard from helicopter flight manuals. "Avoid descent rates of 800 fpm (feet per minute) or greater at airspeeds less than 40 KCAS," it said, "KCAS" being the abbreviation for "knots calibrated air speed." Precisely what might happen if a pilot flew beyond that edge of the envelope wasn't spelled out in the MOTT's flight clearance placard, but there was no need to go into detail. The rule was labeled a "Warning," which meant failing to observe it risked loss of the aircraft and death. For pilots, "Warning" is the flight manual equivalent of a skull and crossbones.

At his May 9 news briefing, McCorkle was asked whether the Osprey that crashed had been "descending within the flight envelope."

"He was descending over a thousand feet per minute," McCorkle said, noting that the recommended limit was no more than 800 feet per minute at 40 knots or less. Why the pilot had descended so fast was still being studied, McCorkle said. The right rotor of the Osprey, he added, might have gone into vortex ring state only when the pilot moved his control stick to the right four seconds before the crash. "I think that that's probably what caused it," McCorkle said.

"Is it correct to say that pilot error is to blame for this accident?" a reporter asked.

"No, it's not correct to say that," McCorkle said. "I would really appreciate it if you wouldn't speculate on that until after the mishap board has reported out. We feel like we have enough information to say that it was not mechanical. There are a lot of things the board is looking at. And why was the pilot at this rate of descent? Why was he in this position at this time? And it would be very inappropriate at this time to say that it was pilot error."

The main thing McCorkle wanted people to understand was that the crash wasn't being blamed on a flaw in the Osprey. Developmental test pilots at Pax River were going to do a full range of tests to explore where the edge of the Osprey's envelope for going into vortex ring state lay, he said. Meanwhile, OPEVAL would go on. "We have waited really a heck of a long time to put the airplane back into the air," McCorkle said.

The Right Stuff

Once upon a time, test pilots like the famed Chuck Yeager tugged on a helmet and squeezed into a flight suit, strapped on an X-model aircraft, then bet their lives they could find the edge of its envelope without having to punch out or ride the experimental machine into the ground. Those days are long gone. Today's test pilots still fly to the edge of the envelope. They still need "the right stuff"--steady nerves, quick reflexes, maybe a little swagger in their walk. They still climb into new or modified aircraft and try things no one else has ever done with them. Today's test pilots, though, no longer routinely fly into the unknown. They don't even fly as often they work on the ground. A test pilot today is more likely to be found manipulating a keyboard and mouse than a stick and throttle. He--they are still mostly men--is less likely to be sitting in a cockpit than in a meeting with engineers or at a desk, analyzing data and planning flight tests in meticulous detail.

Each step in a modern test flight is scripted on a "test card," which is carried on a clipboard strapped to the pilot's knee for easy reference while airborne. After a flight, the pilot writes a detailed report, which he and the engineers will go over in yet another meeting. The report may rely in part on tape recordings of observations the pilot spoke into a microphone as he flew. It will certainly rely on data gathered during the flight by onboard instruments that instantly and constantly record not only the machine's altitude, speed, pitch, yaw, roll, and other motions but its every moan and groan. The instruments radio the data in "real time" to a platoon of engineers on the ground whose job is to assess the results as they come in and watch for signs of danger. The engineers will warn the pilot to knock it off if they see him flirting with trouble. The era when the military was willing to risk a pilot's life or a multimillion-dollar aircraft in a test faded into history with the advent of computerized flight simulators. Today, pilots "fly" dangerous tests first in SUV-sized machines that mimic real flight with astounding fidelity, yet without ever leaving the ground. Equipped with the same cockpit as the aircraft to be flown, the best of such computerized simulators can project on a screen beyond a mock windshield a virtual-reality display of nearly any geographic location as seen from any altitude. Runways, buildings, mountains, rivers and trees are depicted faithfully, in living color, the way they would appear from an aircraft in a climb, a bank, a dive. Some simulators ape the motions of flight faithfully enough to produce vertigo and airsickness. Based on calculations fed into their computers, simulators can be programmed to replicate how an aircraft will behave in almost any circumstance. Flying the aircraft itself is the only way to prove the calculations were correct, but as a rule, test pilots today aren't betting their lives when they go out and fly.

The Osprey's High Rate of Descent tests were an exception to that rule. The pilots who flew them would venture into that region on the map marked "Here Be Dragons." You could die there.

The HROD tests would be dangerous because vortex ring state was largely a mystery. The phenomenon was hard to describe, much less predict, partly because so little research had been done on it in the six-decade history of the helicopter. Beyond that, no one had ever devised an entirely reliable way to predict all the air flows created by rotors. Like the weather, there was a nearly infinite number of variables that could affect them--the configuration of the aircraft, the speed and direction of the wind, the aircraft's altitude, the rotor's angle of attack. The flows around an airplane wing, which moves into clean air constantly, can be predicted with great accuracy. The flows around a rotor, which moves in a circle but might be stationary or moving forward or backward or sideways as it rotates, are devilishly more complex. This makes engineering rotorcraft an art as well as a science. The pilots and engineers in the Osprey program were certain the aircraft's high disk loading made it far less likely to go into vortex ring state than critics assumed. The only way to prove it, though, was to take an Osprey aloft and go find its vortex ring state boundary. Based on calculations and the tests done in 2000, the engineers and pilots were confident an Osprey could get out of vortex ring state simply by tilting its rotors into clean air. If they were wrong, though, someone could die trying.

The Osprey suddenly snap-rolled right more violently than Macdonald had ever seen it do. Instinctively, he pushed the stick left as the roll began but the Osprey didn't respond.

Tom Macdonald, as the Osprey program's chief test pilot, decided he should be the pilot-in-command for each of the dozens of flights planned in the second series of HROD tests. His copilot most often would be Steve Grohsmeyer of Boeing or Bill Leonard of Bell, though Macdonald always would have the controls. Only the two pilots would be aboard; there was no reason to risk more lives by having engineers or crew chiefs in the back.

The tests began only six months after the Osprey's return to flight partly because engineers had to come up with a piece of hardware to accurately measure the Osprey's forward speed at less than 40 knots. Then, from November 2002 to July 2003, Macdonald and his copilots did sixty-two HROD tests, flying a total of 104 hours over a restricted flight range between the towns of Cambridge and Salisbury on Maryland's eastern shore. Macdonald would climb to 10,000 feet, then tilt the rotors up into helicopter mode and slow to a target airspeed. As Macdonald held it there for a bit, a challenge in itself, the copilot would put his hands on his own set of controls, just in case. To duplicate the way the Osprey that crashed at Marana had been flying, Macdonald would lower the landing gear, tilt the nacelles back to 95 degrees, and start reducing power. The Osprey would begin to drop. Macdonald would let it fall until they hit a target rate of descent, then adjust the power to hold the Osprey at a steady sink rate. At that point, still descending, Macdonald and his copilot would talk into their microphones about the Osprey's stability and handling, the quality of the ride, and whether they heard anything unusual. They were looking for ways a pilot might detect the onset of vortex ring state before getting into it. They repeated the flight profile over and over during those months, taking their measurements at every 500-foot increment of sink rate at a series of ever slower airspeeds.

As predicted, they found it hard to put the Osprey into vortex ring state. The boundary for a helicopter was a sink rate somewhere around 800 feet per minute at 40 knots or less of forward speed. Macdonald had to let the Osprey sink at least 2,500 to 2,600 feet a minute at 40 knots before it would near vortex ring state. Even at slower forward speeds, the boundary was a sink rate of around 1,700 feet per minute. He and his copilots weren't actually trying to lose control of the Osprey, they were just trying to find the edge of the envelope, the point where they felt vortex ring state coming on. They got there a number of times without incident. "The thrust would begin to oscillate," Macdonald told me. "A little up and down motion would settle into the aircraft that we weren't commanding." The Osprey would rock a little bit in some cases, and at the lowest speeds they tested, as slow as 10 knots forward speed while plunging toward the ground, the pilots would hear "this eerie howling and audio sound of the air rush," Macdonald said. "We'd just get really silent and quiet." Eleven times during the tests Macdonald flew, one of the rotors went into vortex ring state and the Osprey did a sudden, uncommanded roll--seven times to the right, four times to the left. Each time, Macdonald was able to recover by pushing the thumbwheel switch to tilt the nacelles forward and put the rotors into undisturbed air. Two seconds was usually all it took. Those seconds, though, gave Macdonald and his copilots some hairy moments.

Sink Rate, Sink Rate

The hairiest was on July 17, 2003. The tests already had achieved their primary goal--charting the Osprey's envelope for vortex ring state--a couple of months earlier. Based on that envelope, the program had developed warning devices for the Osprey to alert pilots when they were flirting with vortex ring state. One was visual, a red light on the control panel in front of each pilot that would flash SINK, SINK if an Osprey exceeded a safe rate of descent. The other was a recording of a woman--a device pilots call a "bitching Betty"--who would be heard in the pilot's headset saying "sink rate, sink rate" in an urgent monotone if the limit were exceeded. The HROD tests were continuing, though, because Navair was trying to satisfy key critics that the tests had been adequate. That July 17, Macdonald and Grohsmeyer were flying 7-10 knots and descending at more than 2,300 feet per minute, well beyond the vortex ring state envelope already established. They were dropping like a rock while a special test device alternated the lateral tilt of each rotor to see if that would prevent vortex ring state. Macdonald was on the radio with an engineer on the ground when the Osprey suddenly snap-rolled right more violently than Macdonald had ever seen it do. Instinctively, he pushed the stick left as the roll began but the Osprey didn't respond. By the time Macdonald recognized what was happening, the Osprey was flying on its side, left wing up and right wing down, and spiraling toward the ground ever faster. Macdonald pushed the thumbwheel to tilt the nacelles forward as fast as they would go, all the way to airplane mode. The seconds it took seemed like minutes, but finally he regained control and straightened the Osprey out. For a moment, there was silence in the cockpit and over the radio. Macdonald, Grohsmeyer and the engineers on the ground knew the pilots had just had a close call. If the Osprey had rolled all the way upside down in helicopter mode, there was no telling what damage they might have done to the aircraft--or whether they could have regained control at all.

After Macdonald and Grohsmeyer landed, the program office and the pilots decided they had taken the HROD testing of the Osprey far enough. The Osprey's boundary for vortex ring state had been established beyond any doubt, and studied more than that of any rotorcraft in the world.

Three months later, at a dinner in Los Angeles, the Society of Experimental Test Pilots gave Macdonald its highest honor, the Iven C. Kincheloe Award for "outstanding professional accomplishment." The citation said Macdonald had flown "every flight in a test program where no test pilot has been before." Chuck Yeager was in the audience that evening. He shook Macdonald's hand.
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danon5
 
  2  
Reply Sun 11 Apr, 2010 02:59 pm
@High Seas,
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. I am familiar with the things your article mentioned. We called the transition from the "hover" mode in the helicopter to actual forward flight the --- "translational" part of flying a helicopter. During that part of the flight, the "downward" thrust that produced lift and kept us in the air was "Translated" to "forward" thrust that resembled flying a "fixed wing" airplane. In other words at a certain speed the helicopters "lift" transforms from "down" to the air beginning to flow over the roters - which are the "wings" on a helicopter. During this time there are a few seconds of turmoil - and "shaking" of the entire aircraft.
Been there - seen it - felt that - and done them...... er, something like that.
Oh, that's when the bullets started coming my way and then I turned on the Mini Gun - and got the Hell out of the way of the Gun Ships. But, that's another time in history.

Thanks Helen.

 

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