Calstar Pilots Test-Drive Tail Rotorless Helicopter

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scannerboy02

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California Shock Trauma Air Rescue (Calstar) pilots flying out of Calstar's South Lake Tahoe base recently tried out the latest design in helicopter engineering - a tail rotorless model called the MD 902.

'This is one of the most advanced helicopters in the world,' said Tom Pandola, director of operations since March 2007 at the Calstar 6 base housed at the South Lake Tahoe Airport.

As often as not, when someone is badly injured in a car wreck in Placerville, has broken a leg on a Lake Tahoe ski slope or suffered a heart attack in Cameron Park, Calstar will be called in to quickly transport the victim to the closest medically appropriate hospital or trauma center.

'The first 60 minutes following a traumatic or life-threatening event, such as an accident, fall, heart attack or stroke, are critical,' said Pandola, who worked with the Los Angeles City Fire Department for 25 years before moving to Tahoe. 'Timely access to the appropriate medical treatment affects not only survival rate but also severity of after-effects and disability.'

But in El Dorado County, where the level of care needed after a medical emergency can easily extend beyond the closest hospital's capabilities, getting appropriate treatment in that 'golden hour' can be a challenge.

This new model aircraft will be put to good use in El Dorado County where much of the region is situated at elevations that can be 'more challenging than usual for helicopters to fly due to thin air density,' making the MD 902's capabilities highly valued, Pandola said.

In turn, the aircraft's heightened level of safety and dependability can help drive down the time it takes to get a patient to an appropriate medical facility, he added.

The idea of a civilian air ambulance service took off in the late 1970s and early 1980s, after the Vietnam War raised awareness that the quicker you can get a soldier into surgery, the better his chances of survival. There, in the surgical tents behind the lines of battle, the concept of the 'golden hour' was born.

The first aircraft used as an air ambulance was the Concord in 1984. Over the next several years nonprofit air ambulance organizations sprouted up around the country, including Calstar, which opened its eighth base in South Lake Tahoe in 2001 (Calstar covers most of Northern California, as far north as Ukiah and as far south as Santa Maria).

Pandola's crew was selected to test the MD 902 under the assumption that if the bird could withstand the rigors of mountain flying, where wind and weather patterns are unpredictable, it would do well everywhere else Calstar flies.

So far, the new chopper 'has performed at optimal levels, meeting the challenges of serving a mountainous area,' Pandola said.

What makes this model unique, according to Calstar 6 pilot Mark Alley, is the helicopter's exceptional power and twin engine reliability (with twin engines, the bird can fly over water), smooth ride and NOTAR system, which is the technology used to control the aircraft without a tail rotor.

The MD 902 'uses an individual fan and drive system to maintain stability' ordinarily achieved with a tail rotor, said Alley, who maintains Calstar 6's fleet of birds when he is not flying them.

Because there is no tail rotor, the aircraft's safety rating 'has gone way up' over previous models, Alley said.

Another advantage of the new aircraft is its interior, Pandola said, which is larger than previous models and can hold two patients while providing 'increased accessibility of the patient by the flight nurse crew (of two), and allows them to perform life saving procedures in flight more easily than in a smaller cabin area.'

'It's a great EMS platform because the new technology serves both the crew and patient needs extremely well,' said another Calstar pilot, Mark Davis.

Flight nurses Kelly D'Agostini and J.J. Fielding agree that the MD 902 is to helicopters what a Rolls Royce is to automobiles.

'It's so much quieter, which is really nice for both the patients and the flight nurses,' D'Agostini said.

Because there is no tail rotor and the main rotor has five blades instead of the more common three- or four-blade rotor, the MD 902 is extremely quiet and stable, Pandola explained.

Calstar's flight nurses are among the most highly trained in the country, more highly trained than the usual EMS provider or paramedic, Fielding said. 'We're like a flying emergency room,' she added, saying that she and her colleagues can perform many of the same procedures done in a typical ER.

Both nurses began their lengthy nursing careers in hospitals, D'Agostini working in critical care at Mercy San Juan and Fielding working ICU units at two local area hospitals as well as being a traveling ER nurse.

Both women, whose lifelong dream has been to become a flight nurse one day, applied with Calstar because they love their careers and they love to fly. They said they like the variety of the cases they work along with the autonomy and responsibility that comes with treating patients in critical care situations before hospital care is accessible.

With the MD 902's test period complete, Calstar is in the process of purchasing five of the aircraft, thereby enhancing the organization's ability to 'save lives, reduce disability and speed recovery for victims of trauma and illness through rapid transport, quality medical care and education,' which is the nonprofit's mission statement.

'As a nonprofit, we don't need to make money, we just need to make enough money,' Pandola said.

As such, Calstar is making its services available through memberships, which, along with donations, help the organization pay salaries and purchase state-of-the-art equipment. For membership information, contact Calstar Membership Program at 1-888-207-LIFE (5433).


http://www.mtdemocrat.com/story.php?id=101.1
 

scannerboy02

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We are sending Dann Shively and LiveCopter 3 HD to Tahoe to cover this today.
 

linuxwrangler

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The NOTAR has been around for a while and is a pretty neat idea. It uses the Coandă effect, AKA boundary-layer deflection, to deflect the main-rotor downwash to create the necessary counter-torque.

One effect of this is that when you increase main-rotor thrust, your anti-torque increases naturally resulting in, I'm told, an easier to fly aircraft.

It also eliminates a bunch of driveshafts, gearboxes, and other complexity. And without the noise from the fast-spinning tail-rotor interacting with the main rotor, they are much quieter.

And with over half or helicopter accidents involving the tail-rotor, getting rid of it is a good thing.

The park a couple blocks from me is a designated landing area for REACH and CalSTAR and the scanner sometimes gives me enough advance notice to walk over and get good pictures of the 'copters in action.
 

trooperdude

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Overview:
http://www.airliners.net/info/stats.main?id=116

And you can support CalStar here:

http://www.calstar.org/membership.html



0113735.jpg
 
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trooperdude said:
I think they have an order for 5

Here's an old RR thread on Air Medical Frequencies:
http://www.radioreference.com/forums/showthread.php?t=24549

Funny reading my post in that thread

your sure about that? The only helo's Salinas use is the CHP H70 and Star 2 from San Jose before it crash. Salinas PD and Sheriff never had money for one and nerver will have money for one.

Now they have 2
 

trooperdude

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ScannerDude244 said:
Funny reading my post in that thread

your sure about that? The only helo's Salinas use is the CHP H70 and Star 2 from San Jose before it crash. Salinas PD and Sheriff never had money for one and nerver will have money for one.

Now they have 2

I was talking about CalStar, not law enforcement or Salinas.
 

Scanman6

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Cool Bird

That new bird is cool. I hope it will fly to the Med Center, I work nearby and can't wait to see/hear it in person. I thought I heard the calsign Calstar 6 landing at McClellan today. I bet it's a quiet ship. The Star bird is pretty qiet, but for the tail fan. It's a cool looking ship too boot. Thanks for the posts all.
 

Scanman6

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I saw It Myself.

Well, I didn't have to wait ling. Calstar 6 landed on the Med Center Pad near my work and I had the pleasure of seeing it and barely hearing it. As expected, it was quiet. I even caught it on video. I'm posting this from work and will edit and post tonight when I get home. Look for it if you wish at www.youtube.com/SHANESTER6. Cheers
 
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DPD1

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You'd think the NOTAR system would have caught on a lot more by now. The first 500 series ships started becoming available around 91, and the first test ship was an OH-6 all the way back in 1966. But there's some technical drawbacks to the system. Plus, I think MD products have suffered popularity in general over the years. EADS has really been dominating... Mainly because the Bell and Hughes/MD designs were a little tired up until recently. Maybe these totally new designs and some improvements on NOTAR will help it become more popular finally.

Dave
www.DPDProductions.com
Antennas & Accessories for the RF Professional & Radio Hobbyist
 

SCPD

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The NOTAR has been around for a while and is a pretty neat idea. It uses the Coandă effect, AKA boundary-layer deflection, to deflect the main-rotor downwash to create the necessary counter-torque.

One effect of this is that when you increase main-rotor thrust, your anti-torque increases naturally resulting in, I'm told, an easier to fly aircraft.

It also eliminates a bunch of driveshafts, gearboxes, and other complexity. And without the noise from the fast-spinning tail-rotor interacting with the main rotor, they are much quieter.

And with over half or helicopter accidents involving the tail-rotor, getting rid of it is a good thing.

The park a couple blocks from me is a designated landing area for REACH and CalSTAR and the scanner sometimes gives me enough advance notice to walk over and get good pictures of the 'copters in action.

This being the case then how is yaw controlled, that is, enough to turn the aircraft? The way you explained it the downdraft matches the torque of the rotor. To affect yaw on a ship with a tail rotor, wasn't the RPM of the tail rotor increased or decreased to affect whether yaw to the left or yaw to the right resulted?

Helicopters are so complex that it is difficult to understand how they are controlled mechanically. I just know when flying in them, the pilot was constantly moving, especially when hovering - the ship may not appear to be moving but the pilot sure is! I'm told it is like trying to ride a unicycle while juggling and balancing a beach ball on your nose. This helicopter being easier to fly might be like eliminating one or two of the balls being juggling.
 

rhvfd10

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I actually had a chance to land CS 6 in July (injured Marine to CVMC in Gardnerville, NV) and had a chance to talk to the pilot as he was waiting for the crew to clear from the ER. (careflight's pad in G'ville has a big padlock on it and it wasn't worth breaking so we landed him in the adjacent street) It's quite a neat system and the biggest operational difference compared to most of the CS fleet is the loading from the right side as opposed to the rear.

I know Careflight of Reno, NV has or had a similar tailrotorless model at one point though I haven't encountered it in the field in years.
(I found a newslink showing a photo of Careflight's tailrotorless helicopter but looking at their website I don't think they currently fly one)

http://www.newsreview.com/reno/Content?oid=20213
 
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JayMojave

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Hello Exsmokey and all:

Yeah thats a great question I believe. They would have to have the exhaust running thru a Orifice or bypass some of the exhaust energy to allow the pilot to increase the exhaust to allow for the yaw control, or some other way???

That would be neat to know about that, maybe I'll do a Google search, and look around.


Jay in the Great Mojave Desert.


Exsmokey said:

This being the case then how is yaw controlled, that is, enough to turn the aircraft? The way you explained it the downdraft matches the torque of the rotor. To affect yaw on a ship with a tail rotor, wasn't the RPM of the tail rotor increased or decreased to affect whether yaw to the left or yaw to the right resulted?
 

linuxwrangler

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This being the case then how is yaw controlled, that is, enough to turn the aircraft? The way you explained it the downdraft matches the torque of the rotor. To affect yaw on a ship with a tail rotor, wasn't the RPM of the tail rotor increased or decreased to affect whether yaw to the left or yaw to the right resulted?

Actually the *main* reason for the tail-rotor is to counteract the torque of the main-rotor. Without it, the 'copter would just spin in the opposite direction of the main-rotor. The pedals adjust the pitch of the tail-rotor blades to increase or decrease the anti-torque causing the helicopter to rotate.

Various actions of the pilot such as increasing or decreasing the collective (overall pitch of main-rotor blades) also affect the torque so the pilot is constantly "dancing" on the pedals to keep things in balance.

The notar has a fan in the tail-boom to push air through slots positioned to use the coanda effect to cause the downwash to "stick" to and get bent around the boom in such a way as to counter the main-rotor torque. A happy benefit is that the more the downwash, the more the anti-torque so the pilot doesn't need to work as hard. Instead of adjusting the tail-rotor pitch, the amount of anti-torque is adjusted by the amount of air blown out through control slots at the rear of the boom.

One problem is that in forward flight, the air is not just traveling down over the boom but is substantially moving back along the boom. This is why the notar has the characteristic "H" shaped tail with rudders.

Another method of dealing with torque is to use two main-rotors. The Russian Kamov Hormone, Helix and Hoodlum use coaxial rotors turning in opposite directions. You think standard helicopters are complex, these have gobs of things to go wrong.

Even weirder looking is the Russian Kamen Huskie which uses two intermeshed main-rotors. The rotors are mounted at a slight outward angle so the right-side blade passes just over the top of the left-side hub and vice-versa. Looks like a big egg-beater.

Of course the huge tandem-rotor Chinook and Sea Knight machines also lack tail-rotors.

Wikipedia has some good pages.

http://en.wikipedia.org/wiki/NOTAR
http://en.wikipedia.org/wiki/Coandă_effect

Helicopters are so complex that it is difficult to understand how they are controlled mechanically.

Airplanes fly by using aerodynamics. Helicopters fly by beating the air into submission. Flying rotorcraft involves a number of interesting problems. Just a few:

In doing its anti-torque job, the tail-rotor also pushes the aircraft sideways. To hover in place, the pilot must actually fly slightly sideways the other way to counter the push of the tail-rotor. Viewed front-on, a hovering helicopter often looks slightly tilted.

Then, as you speed up in forward flight, the advancing blade generates progressively more lift while the retreating blade generates progressively less. The pilot must compensate. Additionally, the advancing blade gets closer and closer to supersonic while the retreating blade gets closer and closer to stopping relative to the air passing by the helicopter. These issues limit the theoretical top speeds of helicopters.

Also, the main-rotor is a big gyroscope. And if you recall high-school physics, when you try to tilt a gyroscope in one direction it will tilt in a direction 90-degrees to the applied force. Fun, eh?

A helicopter is much more efficient in forward flight than in hover so the flight service-ceiling is much higher than the hover service-ceiling. And like all aircraft, they can lift more in ground-effect (close to the ground) than out of it. As such, high-altitude helicopter departures often involve lifting off in ground-effect then building up sufficient forward speed to allow the machine to lift out of ground-effect.

About three years ago, helicopters conquered the final frontier - landing on and departing from Mt. Everest:
http://www.everestnews.com/stories2005/everestcopter05272005.htm
http://www.greatoutdoors.com/published/helicopter-on-everest-makes-history
 
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