Notar helicopters and autorotation?
Hell man surely you jest?? You really think doing aerobatics would give you time to be looking inside at the rad alt to see that you're 20' off the ground? What would you suggest you set the bug to as a warning when doing aerobatics then? 
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Hmmmmmmm seems by that article the NOTAR does not auto so good, more like a greased anvil. Actually there is no such thing as a NOTAR, its just that the anti-torque control system is hidden from view, with some major disadvantages; does not work at altitude & gobbles more power than a Fenestron. But wow damn quiet 
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I wouldn't say that NOTAR doesn't auto so good, but I would probably say that the USBP 600's and maybe even all 600's don't auto so good. I did not find them unpleasant at all to autorotate (to touchdown and up to max internal gross weight) in. One thing that has changed in recent years is the MR blades. There is signifigant differences in the lift capability and the autorotation charachteristics of a 369, 500N or 600N with blades produced by HTC (current factory blade) and the blades that were produced by Boeing (and before that MDHI or Hughes).
The 600 was an eye-opener the first time you did an auto, but once you learned the techniques was not a problem. You definatly did not want to doze off while flying though- you have to stay on your game.
Remember, in true autorotation you are not using anti-torque, only at most a little anti-friction. Guys that bitch about yaw at the bottom are landing with the engine driving the rotor (maybe the technique needs improved) or doing a power recovery (probably from a lower than 100% NR) If the NR is above 100% when you join the needles, you won't get a yaw. If you touchdown without the engine driving the rotor you will not get an uncontrollable yaw either.
The USBP disliked the 600 for more than just autorotation charachteristics. The biggest problem was trying to replace the beloved OH-6A with the 600. Too different of animal to compare. After you get a firm dislike for something, anything is better and it is hard to change minds that are made up.
There is such a thing as NOTAR, it is even trademarked! You are correct, NOTAR does not work at altitude, I have never landed or hovered above 12,500 Hd feet in a NOTAR (MD902 and MD600). But up to 12,500 I can say it worked every bit as well as tail-rotor machines I have flown at comperable weights.
The 600 was an eye-opener the first time you did an auto, but once you learned the techniques was not a problem. You definatly did not want to doze off while flying though- you have to stay on your game.
Remember, in true autorotation you are not using anti-torque, only at most a little anti-friction. Guys that bitch about yaw at the bottom are landing with the engine driving the rotor (maybe the technique needs improved) or doing a power recovery (probably from a lower than 100% NR) If the NR is above 100% when you join the needles, you won't get a yaw. If you touchdown without the engine driving the rotor you will not get an uncontrollable yaw either.
The USBP disliked the 600 for more than just autorotation charachteristics. The biggest problem was trying to replace the beloved OH-6A with the 600. Too different of animal to compare. After you get a firm dislike for something, anything is better and it is hard to change minds that are made up.
There is such a thing as NOTAR, it is even trademarked! You are correct, NOTAR does not work at altitude, I have never landed or hovered above 12,500 Hd feet in a NOTAR (MD902 and MD600). But up to 12,500 I can say it worked every bit as well as tail-rotor machines I have flown at comperable weights.
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after spending a few hours throwing the 600 at the ground at mesa with mfriskel i didnt have any problems
i survived and so did the helicopter when i had a engine stop at cranfield [its a real quiet helicopter when the donkey stops ]
i survived and so did the helicopter when i had a engine stop at cranfield [its a real quiet helicopter when the donkey stops ]
Just looked at the video, auto was crap, flying at what looks like down wind at less than 500 ft when entered, the " wings" werent even level when the ac flared and the flare was way way too late. Mind you impressed with the undercarriage !
Mark are htc blades with the new erosion strip( eliminating that " valley" behind the smaller strip) back to the level of the old MD blades ? Certainly having filled and faired my 101 htc blades put about 8 kts on the speed of a D model.
Mark are htc blades with the new erosion strip( eliminating that " valley" behind the smaller strip) back to the level of the old MD blades ? Certainly having filled and faired my 101 htc blades put about 8 kts on the speed of a D model.
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I can't answer to the "new" abrasion strip as I haven't flown them. If it fixes the problems it is a good thing that has been a long time comeing. Filling and fareing was a good "mod" to the abrasion strip, but by no means a fix to get back to the performance of the Boeing blades.
The other odd thing about those blades was the honeycomb patch that slightly deformed the outer portion of the blade. It had to have some aerodynamic effects on the blade.
If the "new" abrasion strips get you back to no more than 2 or 3 degrees of down tab in the major sections of the blades I would say they are better, but if you are still having to use nearly 5 degrees of down tab I would say no.
The other odd thing about those blades was the honeycomb patch that slightly deformed the outer portion of the blade. It had to have some aerodynamic effects on the blade.
If the "new" abrasion strips get you back to no more than 2 or 3 degrees of down tab in the major sections of the blades I would say they are better, but if you are still having to use nearly 5 degrees of down tab I would say no.
There is background to this.
The USBP never selected the MD600 - it was decided from the start that it was unsuitable for their mission.
They selected the AS350. Unfortunately at that time the European manufacturer had been involved in what US Authorities thought to be shady trading [I am not sure of the exact circumnstances without more research] and they were forbidden to buy the EC product.
As soon as the period of prohibition finished the USBP were back at Eurocopter's door.
So it was not really the fault of the 600 it did not meet the spec., it was never selected against that specification, it was second best, and will have had its enemies from the start.
The USBP never selected the MD600 - it was decided from the start that it was unsuitable for their mission.
They selected the AS350. Unfortunately at that time the European manufacturer had been involved in what US Authorities thought to be shady trading [I am not sure of the exact circumnstances without more research] and they were forbidden to buy the EC product.
As soon as the period of prohibition finished the USBP were back at Eurocopter's door.
So it was not really the fault of the 600 it did not meet the spec., it was never selected against that specification, it was second best, and will have had its enemies from the start.
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PANEWS, you know that for FACT, or just what you would like to think? I am curious about the "prohibition" period. Never heard of that one. The USBP did select the MD600, that is why they were ordered and paid for. It was not a suitable replacement for the OH-6, but it was not marketed nor sold as a replacement, it was to suppliment in a different mission. Unfortunatly, the one that is in the air, or out of the hangar is the one that is used. What happens then is trying to compare apples to oranges, and the guys who liked apples didn't like what they had- they were also very vocal. The guys who liked oranges just kept doing their jobs.
USBP did not have good luck with the AS350 from the early 90s, well before delivery of the first MD600. I remember one rolling down a mountain in Arizona that was trying to do a job that an OH-6 would do just fine.
I also believe they have suffered fatal accident(s) in their AS350 fleet, but not in the MD600 fleet.
USBP did not have good luck with the AS350 from the early 90s, well before delivery of the first MD600. I remember one rolling down a mountain in Arizona that was trying to do a job that an OH-6 would do just fine.
I also believe they have suffered fatal accident(s) in their AS350 fleet, but not in the MD600 fleet.
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"It's the softer option. Power on run-on landing at **knots?
Not possible without at least one engine of course.
The auto without the fan has probably never been proven nor does it have to be. The power on option can probably be demonstrated with a "zero anti-torque" setting.
Read this download about a 900 in Japan."
RVDT- It is really not possible to truely demonstrate a fan failure as minimum fan pitch in all three models is still a signifigant amount of airflow. The the thruster is open straight down or up to give you no thrust from the thruster. This will give you good COANDA effect and some anti-tq when the acft slows. The other control, the VSCS or vertical stabilizers will have some angle of incidence. With a true fan failure you would be able to hold full left pedal in a 500/600 and have anti-tq to quite a low airspeed. If I was an engineer, I would have a switch in the 902 that would allow a pilot to set any of three set angles on the VSCS for emergency. Could be nice for either stuck thruster or failed fan.
The Japan accident was very interesting. The pilot flew that acft for over an hour before attempting to land. He had good control until he performed a fairly tight turn to final and slowed the airspeed to a very slow forward speed and a slight climb. At that point the acft started to spin and it was "Mister Toad's Wild Ride" from 200 feet AGL. If you ever get a chance to see that video, it will open your eyes for sure. The structure of the acft saved those two guys bacon for sure.
Not possible without at least one engine of course.
The auto without the fan has probably never been proven nor does it have to be. The power on option can probably be demonstrated with a "zero anti-torque" setting.
Read this download about a 900 in Japan."
RVDT- It is really not possible to truely demonstrate a fan failure as minimum fan pitch in all three models is still a signifigant amount of airflow. The the thruster is open straight down or up to give you no thrust from the thruster. This will give you good COANDA effect and some anti-tq when the acft slows. The other control, the VSCS or vertical stabilizers will have some angle of incidence. With a true fan failure you would be able to hold full left pedal in a 500/600 and have anti-tq to quite a low airspeed. If I was an engineer, I would have a switch in the 902 that would allow a pilot to set any of three set angles on the VSCS for emergency. Could be nice for either stuck thruster or failed fan.
The Japan accident was very interesting. The pilot flew that acft for over an hour before attempting to land. He had good control until he performed a fairly tight turn to final and slowed the airspeed to a very slow forward speed and a slight climb. At that point the acft started to spin and it was "Mister Toad's Wild Ride" from 200 feet AGL. If you ever get a chance to see that video, it will open your eyes for sure. The structure of the acft saved those two guys bacon for sure.
