Odd Helicopter - Looking for ID

[SimonM]

Hoping there's a helicopter expert here who might be able to help.

While driving down the M1 from Brisbane to the Gold Coast, MrsM spotted an odd helicopter following the road, also going south. By the time she pointed it out to me, it was quite a way off, but the two odd things were that it appeared to have contra-rotating rotor blades and that the body of it was very slim. Still a full size machine though and definitely not a toy.

We do see a lot of helicopters over our house on the Coast, but I've never seen one like this. Can anyone suggest what it might have been? A bit early for a Sikorsky X2?

X2 Technology

 

[markis10]

What time?

 

[markis10]

It was a Kaman K1200



NZ Civil Aircraft: ZK-HEE........he he he

 

[SimonM]

What time?

I'm not 100% sure, but approx 2:45pm (Qld time) today (5-Jan-11).

 

[markis10]

Yep, was last on BNE radar at 2.30, altitude 1000 ft.

 

[SimonM]

It was a Kaman K1200

View attachment 1582

NZ Civil Aircraft: ZK-HEE........he he he

Thanks very much for resolving that. I had a look at Wikipedia and see that it's quite a rare craft. Well spotted MrsM!

 

[markis10]

I have to say its not the prettiest aircraft, if it was Russian they would have at least stuck some rocket launchers and cannon on it.

 

[SimonM]

I have to say its not the prettiest aircraft, if it was Russian they would have at least stuck some rocket launchers and cannon on it.

Do you happen to know what it's doing here?

 

[medhead]

The rotor configuration looks like an accident waiting to happen.

 

[samh004]

That is one ugly helicopter!

But what does straitman think of it?

 

[markis10]

Do you happen to know what it's doing here?

Got any Chimneys that need demolition down the coast??

Helicopter-mounted wrecking ball - PPRuNe Forums

Yes, it is the very same chopper you saw!

 

[SimonM]

Got any Chimneys that need demolition down the coast??

Helicopter-mounted wrecking ball - PPRuNe Forums

Yes, it is the very same chopper you saw!

Not that I know, but I'd pay to watch if there was!

 

[straitman]

That is one ugly helicopter!

But what does straitman think of it?

Ugly :!:

The K1200 was designed as a work horse and appears to do a reasonable job of it. I think the article in the link in post #3 is a bit deceptive when they call it a 'Heavy Lift Helicopter.' With a high payload to overall weight ratio it is certainly powerful but with an AUW of only 12,000lb it is only a medium helo at best.

The advantage of the weird main rotor system is that there is no tail rotor required.

General characteristics

• Crew: 1
• Capacity: 6,000 lb (2,722 kg) external load
• Length: 51 ft 10 in (15.8 m)
• Rotor diameter: 48 ft 3 in (14.7m)
• Height: 13 ft 7 in (4.14 m)
• Empty weight: 5,145 lb (2,334 kg)
• Useful load: 6,855 lb (3,109 kg)
• Max takeoff weight: 12,000 lb (5,443 kg)
• Powerplant: 1× Honeywell T53-17 turboshaft, 1,800 shp ()

Performance

• Maximum speed: 100 knots (185.2 km/h)
• Cruise speed: 80 knots (148.2 km/h)
• Range: 267 nm (494.5 km)

Many will be aware of the $1B+ SNAFU of the Sea Sprite which was also built by Kaman.

 

[medhead]

Ugly :!:

thanks.

The advantage of the weird main rotor system is that there is no tail rotor required.

Yep a good advantage that one. My issue is that the rotors appear to be interlocking from the picture. It would be a terrible shame if the "syncro mesh" failed. the Russian stacked contra rotating arrangement would seem to be simpler.

Many will be aware of the $1B+ SNAFU of the Sea Sprite which was also built by Kaman.

my take was that was more avionics/weapons systems problems. Were there mechanical issues as well?

 

[thewinchester]

Ugly - yes, useful - definatly.

Saw this exact helicopter recently on an episode of Worlds Toughest Fixes on Nat Geo, where it was being used to move in and position parts of a ski lift being rebuilt in rugged and hard to access mountain terrain.

According to the presenter and operator, the strange rotor configuration helps it generate more lift and provides stability when dealing with its bread and butter - large loads.

 

[medhead]

According to the presenter and operator, the strange rotor configuration helps it generate more lift and provides stability when dealing with its bread and butter - large loads.

The rotors spin in opposite directions hence counteracting the physics of every action has an equal and opposite reaction. In a single rotor that means the fuselage wants to spin in the opposite direction to the rotor. This is prevented by the tail rotor, however that then takes power from the main rotor.

the twin rotors push against each other and hence no tail rotor required giving more power to the main rotors. They also can have a large area than a single rotor and hence more lift.

Other obvious examples are the chinook and the Russians had a model or two mainly for naval operations.

 

[samh004]

*raises hand* I have a question.

With most helicopters I’ve seen you’re able to duck and get onboard/very close while the blades are spinning, however with this design it looks like the blades would be very close to the ground as they spin. Is that the case?

 

[thewinchester]

*raises hand* I have a question.

With most helicopters I’ve seen you’re able to duck and get onboard/very close while the blades are spinning, however with this design it looks like the blades would be very close to the ground as they spin. Is that the case?

From what I saw of it in operation and the visible warnings on the body, there may be some truth to that.

Normally, most helicopters would be approached safely from the sides. The K1200 specifically has notices advising to approach it from the front only.

 

[russ1]

Dad and Mom with my buddy N267KA
Most of the facts about the Kmax listed in this tread are correct but not the fears (except for a few details)
1) It was originally designed as a multipurpose helicpcopter for military and commercial use. The beam that the rear legs are attached to was designed to carry machine guns and missle launchers like the old Hueys during the Viet nam war.
2) Also the passenger capacity is 3, altought all the literature says 1. There are specially designed seats that attach to the top side of the rear langing gear beam that can be mounted next to the fusalage.

I know all this beacuse I worked with Kmax helicpters for 2.5 years.

Blades
1) When powered off the tip of one of the blades is about 8 feet off the ground, the rest are higher. They use a 2 to 3 ft metal hook to catch a metal loop on the end of the blades in order to attach the tie down ropes. They catch one blade, rotate them until the next blades is next to the ground, catch it and so on
2) When powering up, the blades are still about 8-10 feet off the ground, but may dip closer if the pilot twists the blades during rotation testing. The blades are made of laminated wood and depend on blade twisting and other controls to get lift and for autorotation. During high winds or when the blades are rotating, you only approach the helicopter from the front or back. Otherwise it is safe to approach the helicopter from the sides
3) It is very safe to go up to the helicopter from the front or back when the blades are turning, and is very safe to open the cab when the blades are turning at low rpm

Blade contact and the tranmission
It is impossible for the interloacking blades to hit each other. Many accidents with the helicopter happened do to blade failure, but never due to a timing situation where the interlocking blades hit each other. What you call the timing isn't a matter of timing. The Kmax has a V shaped tranmission, so the transission would have to loose a gear which is impossible, and if you saw the guts of this transmission you would know why

Current use
harvesting lumber, chimney demolition, carrying heaving loads such as airconditioning units to the roof of tall buildings, firefighting using a bambi bucket or the kamax water tank, seismic work - delivering seismic equipment, moving and poring cement in specially design cement hoppers, lifeting moving and placing tall towers for ski lifts and power lines, lifting vehicles and other things from an accident site, and Dubai wanted to equip one with a water cannon (like on fire trucks) to put out fires inside sky scrappers.

 

[SimonM]

Welcome to AFF Russ1 and thanks for the first-hand details about the Kmax.