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Kansas City police helicopter autorotates like a boss

SFOGuy says...

That would be AWESOME if he was. But in actuality---because of the tail rotor still spinning and then how the main rotor blades droop as they slow down (at just about the right height-with no visual profile end o- to chop someone driving a semi or a bus in half)---the entire helicopter is a rotating engine of death until everything comes to a halt...
Thus, the duck and run of people getting out from a chopper. And not duck and run towards the tail rotor specifically.

diggum317 said:

I thought he was raising his hands to say "Hell yeah! D'ya see what I just pulled off?!"

The Slow Mo Guys - Convertible Aerodynamics at 1000fps

blutruth says...

My understanding is that the voltage being sent to the LED headlights is passed through a Pulse Width Modulation (PWM) driver that creates a pulsing effect so that the LED receives a consistent average voltage over time and allows for the control of the LED's perceived brightness. If there is a mismatch between the PWM frequency and the frame rate of the camera, you will see pulsing or flickering. You see the same kind of effect sometimes when a camera records a helicopter and the rotors appear to be stationary like here.

At least I'm pretty sure that's what's going on.

CrushBug said:

Talk to me about why the headlights looked like they were flickering. Some sort of shutterspeed versus LED thing?

The Most Costly Joke in History

newtboy says...

Yes, you did. You said repeatedly that dogfighting capabilities are not needed at all because this fighter won't ever see dogfighting because it never happens since WW1, and all engagement happens at long range and stealth will protect it 100%.
You must have not read, the articles I linked were about air to air engagements, not bombing, and included up to the gulf war.
Again, the F-15 and F-4 as deployed today is not inferior to Russian planes. Only if you compare the original incarnation of the F-15 with the top of the line Russian planes of today, sometimes it comes out on top, sometimes it's specs are worse.
There's no such thing as a real F-35 pilot, only test pilots have ever flown it, and never in real life situations, only pre conceived situations where it still fails the test designed for it to pass.
The F-35 can't dogfight, and it's not even in the US arsenal. Jesus Christ!
The article I listed before cracked was the one with data, the cracked one was simply to show dogfights using guns have happened repeatedly since WW1, in fact at least up through Vietnam including one completely insane example of using the rotor wash of a helicopter and an AK-47 to take out a pair of fighters (which, agreed, sounded made up it was so insane), contrary to your repeated assertion that it hasn't happened at all and never will again. I notice you don't dispute their facts though.


Oh well. Here I thought perhaps reason and facts had finally permeated the fan boy shell. I guess I was wrong. I give up. If you're going to stick with ridiculous positions like 'there's been no dogfights since WW1', and 'the F-35 will out dogfight the F-4' after being proven wrong time and again with real data and test results, there's no logic or fact that will break the shell, so I quit. Don't feel bad, you're in good company with all of congress (but of course, they all got PAID to hold their positions). Enjoy your $2 trillion fleet of useless planes, since no amount of failure or expense can kill the project.

transmorpher said:

I have not agreed that my position is wrong on the performance and capability designs of the F-35 and modern air combat. Please read the rest of my post above.... I'm still saying that dogfights have ended with WW1. I've never said we don't need ANY dog fighting capabilities. I'm saying that it's never the primary design idea of a modern fighter jet. You still have a cannon for back up. Just like soldiers have a side arm and a knife. Just in case you do get caught with your pants down or the main weapon fails at a critical moment.

I have agreed on the waste of money aspect of course. I'll also agree that if test goals are being downsized to accommodate flaws, then that's just terrible. If it's not able to perform to it's design then it's useless.

The F-4 != F-35. I can see why people draw parallels. But that only works if you ignore that absolutely everything on the planes is different, the adversaries are different, and stealth is requirement for survivability. You don't use stealth planes in the way you use an non stealth plane. Have you ever heard of a sniper wearing a ghillie suit run across the open battlefield with a sword or pistol? There were so many tactical mistakes in Vietnam as well. The conditions in which that article talks about are also different. Those planes were flying low and slow for a bombing run. Because they didn't have laser, gps guided bombs, infrared fire and forget air to ground missiles or cruise missiles back in those days. You don't get fog at 40,000 feet. They had to fly that low to get a visual identification of their bombing target. That does not happen anymore either. You scream past at mach 1 above the clouds and the bomb hits where it was programmed to hit. Also the phantoms missiles were unrelaiable. That hasn't been the case since the 80s. And their training was poor. None of that is true these days, and has not been true since the 80s either. That's why every single fighter plane apart from the F-16 (which is made mostly as an export product anyway) has been created to fight at long range primarily. The F-15 which is the main air superiority fighter for the US, is heavy and has a worse maneuverability than any Russian plane. But it's still the most feared plane, with no loses in combat. The article you linked even says that. So it's basically contradicting itself. At the start it says, F-4's lost because they couldn't maneuver, and ends with therefore the US made the F-15 which has worse maneuverability than the Russian planes lol.



Edit: Cracked.com doesn't count as a reputable source for anything, including basic sentences, spelling and punctuation.

Edit2: Here is an article from an actual F-35 pilot that says the F-35 dog fights better than a F-16 since they keep tuning the fly-by-wire parameters. http://theaviationist.com/2016/03/01/heres-what-ive-learned-so-far-dogfighting-in-the-f-35-a-jsf-pilot-first-hand-account/

So even if it came to a dogfighting encounter, the F-35 is still the best plane in the US arsenal for dogfighting.

The Incredible Transforming Osprey

Drachen_Jager says...

Yeah, these things are death traps. They're so useless, the Navy has to send out OTHER helicopters to pre-scout landing zones for the Ospreys. Aside from that, the downblast from the rotors is so powerful, it makes work on a flight deck impossible during takeoffs and landings, as an added bonus, it also makes rappelling so dangerous Marines call it the "elevator of death".

Add to that the enormous cost of $72 million a unit a flight-speed too fast for escort helicopters and too slow for escort jets and a host of other problems and you have a very expensive and cool looking lawn ornament. 35 Billion dollars well-spent, Pentagon.

Russian Drifting

newtboy says...

From my experience, and physics class, that should only be true if your brakes suck. Physics don't lie, and I was taught that static friction is ALWAYS greater than kinetic friction...meaning rolling tires grip better than sliding tires every time. If your brakes are able to grip with more 'stopping' force than the sliding tire produces and still allow 'slip', they should be able to stop you faster than sliding.

Perhaps on ice that's true, or other slippery surfaces where the sensors get confused, or with really bad or broken ABS, but good ABS seriously reduces the distance to stop AND retains control by rapidly (thousands per second) pulsing the braking force up to maximum possible force without stopping the rotation. That should be more stopping force than locked tires can produce if the brakes are in good condition.

I've been in the car when an idiot friend decided to prove it to me, and slammed on his new BMW's brakes at about 70mph. The seatbelt hit so hard I had the wind knocked out of me, and we stopped ridiculously fast (WAY faster than when I've locked up non-abs cars on the freeway...repeatedly). Afterwards, he needed new brakes all around, because they gripped so hard and hot it warped the new rotors, but never locked up the tires...retaining static friction between the road and tire. Dumb...but informative.

Payback said:

Newt, I gotta tell ya, there is no quicker way to stop than locking up all four wheels, other than spinning in the other direction on a dry surface to kill inertia (makes it worse on ice). You just have no control. ABS brake systems actually increase the distance needed to stop, they just provide the ability to control and turn at the same time.

Prototype Helicopter Crash after Catastrophic Failure

rich_magnet says...

Wow, the *fear of how it's going to turn out is intense. Heli crashes usually go very bad. The rotor has so much kinetic energy it often destroys the airframe on even a minor crash.

The latest anti-drone technology

WaterDweller says...

Was the hawk injured? Those drone rotors turn pretty fast, and I've read about people getting cuts from accidentally touching them. I wouldn't be surprised if that hawk was maimed.

Nixie: Wearable Camera That Can Fly

My_design says...

The slap bands don't work because the arms are at angles to each other. Slap bands can only rotate in a straight direction (They are basically tape measure metal), so they wouldn't be able to come back to meet in the center like they illustrate. Also they have the motors all prettily lined up and facing directly off the wrist, that would require the material to be able to twist.

For the rotor size, these are fixed pitch rotors. You can change the pitch of the rotor to give you different flight characteristics and in general you have to match the pitch to the motor to be the most efficient. I may have this reversed, but a lower pitch prop gives you more torque and less overall speed, but a higher pitch prop gives more top speed, less torque. Making a prop that can be injection molded at that size that even works is difficult, making one that is super efficient would be even more so. QC would have to be incredibly exacting. As a gauge, the 2" x 2" quad has 1" props. They can lift it and buzz it around pretty well. Those things were a pain to get correct and I have a hard time imagining anyone making them more efficient than they are. In the case of the 2" quad, we didn't even paint the body because we want to limit the impact on flight time from added weight. All molded in color. That's how sensitive these things can be. There are better motors if you are willing to pay, but even then it may not be enough.
Go Pro records in HD, but doesn't actually broadcast anything (plus it is big enough to keep this thing from flying anywhere). If you want to broadcast video you have to do it in 640x480 tops. To do that you need something like an FPV system that broadcasts on a spread spectrum. If you went bluetooth you have an effect range that is pretty small. Wifi requires more power to get a longer range. A video transmitter system would require a separate device to attach to your phone to receive the signal and translate it to a PPM signal for through the headphone jack. But a VTX is pretty heavy as well.
And things may drain just a little bit of power, but it stacks up. At most you have a 250mAh Lipo battery that can fit in there. That isn't going to buy you a bunch of flight/video time.
Video on the phone is going to be subject to interference, so you would want to record on the quad. this would get you HD quality, but also adds weight, which means more battery draw, which means less flight time.
-B

newtboy said:

I don't understand, why would they have to bend in multiple directions? it seems they need to be straight or curve in one direction. Did I miss something?
I'm estimating the size, about 6" around one's wrist makes it 6" 'wide', and near 3" 'long'...yes the blades seem about 1.25" diameter. You would know more than I about that being enough, but I do know there are different prop configurations for different applications, perhaps they have an ultra efficient prop and motor pair? There are certainly more powerful motors available, if you're willing to pay for them.
Adding blue tooth is minimal in weight and power drain, and the lag shouldn't be an issue in most applications (I wouldn't try making it run a gauntlet of obstacles though).
Camera batteries are pretty powerful today, allow fast drain, and come in small sizes. Maybe not enough yet, commercially available, but certainly possible to make...if you're willing to pay.

For your issues....
1)super thin spring steel could work, but wouldn't look like the plastic they showed. What's the issue with 'slap bands'? They seem perfect.
2) power is an issue, as is flight time. I feel like early adopters would sacrifice flight/record time for the advantage of size...but only time will tell.
3) object avoidance IS an issue. Likely the solution is to limit it to use where there's no obstruction above it and not too much in front. Slight lag isn't an issue, if it's not moving fast. Return to the object it's centered on should be no problem, it tracks an object to film it, it shouldn't be too hard to return to it. Now, catching it while hanging on a cliff....yeah...that's tough.
4)Does not Go-pro already wirelessly send it's video in real time "HD"? They cost under $400.

I'll agree with you, you would be MUCH better off buying a larger one that works NOW instead of sending money in hopes they come out with this super miniature one. That said, I still think this is possible...just expensive and difficult to make work.

Hoverbike Kickstarter Campaign

Stormsinger says...

How long do you figure it'll be before someone loses a hand (or a head) to one of these? The rotor tips are the only danger...especially on one big enough to carry a person. For those full-size babies, any piece of gravel or wood on the ground under it could easily turn into a bullet.

John Oliver Leaves GM Dismembered in Satans Molten Rectum

Sagemind says...

Actually, this is true, but it's also only one of the recall items that GM has issued Recalls for this year.

"It recalled 8,208 of its 2014 cars on May 7, for example, because they might have rear brakes on the front wheels."

"GM says it has informed regulators about two more recalls imminent but not yet announced. The latest batch includes safety belt, air bag, transmission and electrical issues in a range of midsize sedans, full-size crossovers and SUVs, and pickups."


GM's U.S. recalls this year

Below are General Motors' recall of vehicles in the U.S. since Jan. 1

Date, no. of U.S. vehicles, models affected, recall defect

- Jan. 13: 324,970 of the 2014 Chevrolet Silverado and 2014 GMC Sierra for overheated exhaust parts

- Feb. 7 and 25: 1,367,146 of the 2005-07 Chevrolet Cobalt, 2006-07 Chevrolet HHR, 2005-07 Pontiac G5, 2006-07 Pontiac Solstice, 2003-07 Saturn ION, 2007 Saturn Sky, 2007 Opel GT, 2007 Daewoo G2X for ignition switch

- Feb 20: 355 of the 2014 Buick Enclave, LaCrosse, Regal and Verano; 2014 Chevrolet Cruze, Impala, Malibu and Travers; 2014 GMC Acadia for transmission shift cable adjuster

- March 17: 63,903 of the 2013-14 Cadillac XTS for brake vacuum booster

- March 17: 303,013 of the 2009 Chevrolet Express and GMC Savana for airbag

- March 17: 1,178,407 of the 2008-13 Buick Enclave, 2008-13 Chevrolet Traverse, 2008-13 GMC Acadia, 2008-10 Saturn Outlook for airbag

- March 17: 656 of the Cadillac ELR for electronic brake control

- March 28: 823,788 of the 2008-11 Chevrolet HHR, 2008-10 Chevrolet Cobalt, 2008-10 Pontiac G5, 2008-10 Pontiac Solstice, 2008-10 Saturn Sky, 2008-10 Opel GT, 2008-09 Daewoo G2X for ignition switch

- March 28: 174,046 of the 2013-14 Chevrolet Cruze for front axle shaft

- March 28: 489, 936 of the 2014 Chevrolet Silverado, 2014 GMC Sierra, 2015 Chevrolet Tahoe and Suburban, 2014 GMC Yukon and Yukon XL for oil cooler fitting.

- March 31: 1,340,447 of the 2004-06 Chevrolet Malibu and Malibu Maxx, 2004-06 Pontiac G6, 2004-07 Saturn Ion, 2008-09 Chevrolet Malibu, 2008-09 Pontiac G6, 2008-09 Saturn Aura, 2010 Cobalt, 2009-10 Chevrolet HHR for electric power steering

- April 9: 2,191,014 of the 2005-10 Chevrolet Cobalt, 2006-11 Chevrolet HHR, 2007-10 Pontiac G5, 2006-10 Pontiac Solstice, 2003-07 Saturn ION, 2007-10 Saturn Sky for ignition key cylinder

- April 24: 50,571 of the 2013 Cadillac SRX for acceleration lag

- April 19: 23,249 of the 2009-10 Pontiac Vibe (built by Toyota) for air bags

- April 24: 51 of the 2015 Chevrolet Silverado HD and 2014 GMC Sierra HD for diesel transfer pump

- April 29: 51,640 of the 2014 Chevrolet Traverse, 2014 GMC Acadia and 2014 Buick Enclave for inaccurate fuel gauge

- April 29: 56,214 of the 2007-08 Saturn Aura for shift cable

- May 7: 8,208 of the 2014 Chevrolet Malibu and 2104 Buick Lacrosse for brake rotors

- May 14: 111,889 of the 2005-07 Corvette for headlight low beams

- May 14: 19,225 of the 2014 Cadillac CTS for windshield wipers

- May 14: 140,067 of the 2014 Malibu for brake boost

- May 14: 2,440,524 of the 2004-12 Chevrolet Malibu, 2004-07 Malibu Maxx, 2005-10 Pontiac G6 and 2007-10 Saturn Aura for brake lamps

- May 14: 477 of the 2014 Chevrolet Silverado and 2015 Chevrolet Tahoe for steering tie-rod

- May 16: 1,402 of the 2015 Cadillac Escalade for passenger air bag

- May 19: 1,339,355 of the 2009-10 Saturn Outlook, 2009-14 Chevrolet Traverse, 2009-14 GMC Acadia and 2009-14 Buick Enclave for front seat belts

- May 19: 58 of the 2015 Chevrolet Silverado HD and 2015 GMC Sierra HD for loose fuse block

- May 19: 1,075,102 of the 2004-08 Chevrolet Malibu and 2005-08 Pontiac G6 for shift cable (expands April 29 Saturn Aura recall)

Total 18,666,842
( http://www.usatoday.com/story/money/cars/2014/05/20/gm-recalls-fine-goverment/9329481/ )

scheherazade said:

For anyone that hasn't followed what this is about...

This affair was actually about 1 specific issue :
The detent in the key socket rotator was not as strong as it should have been.

( --- Sniped ---)

-scheherazade

Helicopter on road (Only in Russia)

Helicopter on road (Only in Russia)

This little chopper is smokin'

Drone Captures Rare & Unusual Event in the Ocean

How Charlie Sheen Discovered Global Warming

deathcow says...

They're waiting for you Gordon.

In

The Test Chamber


Intercom 1: (feedback)"Testing, testing. (coughs) Everything seems to
be in order."
Intercom 2: "All right, Gordon. your suit should keep you comfortable
through all this. The specimen will be delivered to you in a few
moments. If you would be so good as to climb up and start the rotors,
we can bring the anti-mass spectrometer to 80 percent and hold it there
until the carrier arrives.

Why was HL1 SO good.. why do I still remember all the voices and scenes all these years later.



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