700-kg kite plunges into crowd, injuring 4 people

Police have launched an investigation into the case on suspicion of professional negligence

What about police negligence for letting it go ahead?

The local weather bureau had issued a strong wind warning for Sunday afternoon.

For those of us who are metrically challenged, 700kg is equivalent to about 1,500 pounds. That's a huge kite.

1,500 pounds

That's an expensive kite.

It must have been like watching the Hindenburg come down. I'm glad nobody was killed. Here is a website about Japanese kites for anyone who wants to see what they look like.

http://wordpress.tokyotimes.org/king-sized-japanese-kites/

700 kg, I think it is 70 kg. 700 kg ,That is heavier then a 150 Cesnor The math don,t work out.

700 kg, I think it is 70 kg.

@John

The Japanese media reported that it weighed 700 kg.

Here is footage of the accident: http://www.47news.jp/movie/general_national/post_11752/

John san. I agree with you. Maybe a steel pipe kite? With steel sheet. As body. 700kg is too much

The local weather bureau had issued a strong wind warning for Sunday afternoon.

One would think that strong wind is a pre-requisite for flying such a kite.

But seriously, there must become a point where a kite becomes so unwieldy it is a danger to both those flying it and spectating.

How on Earth they planned to reel it back in one piece is a mystery to me.

I watch the footage last this morning. This has to be a typeo error.

Now we just need someone to land one on the PM's residence.

Wonder how long it wud take for them to find it tho LOL!!!

700 kg? That is one heck of a heavy kite. Isn´t it a typo? 70 kg sounds more belieavable.

At 100 kg each, that's seven baby elephants!

Time to stop having these events if people are nearly getting killed -- and as the article indicates this is not the first time, or else do not allow spectators nearby. And sorry, but people in Japan need to start taking weather warnings seriously. Record breaking temperatures and extreme UV rates and sun and yet, if the date decided on for the Sports Day is Sunday, it MUST be none other than Sunday! Who cares if the kids get sun-stroke?? If the weather forecast indicates strong wind that here means STRONG, and probably gusty -- ie. not ideal for kite flying. It should not have been held.

photo montage of the accident: http://jto.s3.amazonaws.com/wp-content/uploads/2015/05/n-kiteaccident-a-20150601-870x404.jpg

This happened just across the river from my house. The kite is huge and take a big truck to bring the pieces to the event where it is then assembled. It is made from bamboo and very heavy paper or maybe cardboard. 700 kg seems like a lot but it really does weigh that much. It takes a team of people to attempt to get it up in the air (complete with the kite festival princesses who fan it). Yesterday was a crazy windy day which helped it get up quite high but made it difficult to control. They probably shouldn't have let it get up so high. The area they keep roped off for safety doesn't seem like it would be right for how high the kite was flying yesterday. Luckily I watched it from my balcony instead of the festival yesterday.

-1 for safety

Been to the giant kite festival in Hamamatsu and took part in the pre-festival rites. Great stuff, wonderful part of Japanese culture, and it would be a shame to see it disappear - but hey: important safety tip here. DO NOT ALLOW PEOPLE TO STAND UNDERNEATH THE FLYING AREA.

Yikes, that photomontage.

I wonder why they just let people stand and walk around beneath a 700 KG flying monstrosity. Surely the past accidents and some common sense would give some hints to fly it above an empty field or something.

People keep complaining about drones, but it's a kite that ends up doing serious damage...

The problem with rule making in Japan is that it's not generalized.

Drone or kite, the rules should be essentially the same, and people ought be held to account based on the principles involved.

At 700kg it was no longer a kite. It was a glider.

I say, to heck with the negligence charges. Anybody hanging around that thing for seven minutes obviously has no regard for their own safety. So to heck with them. The charges are frivolous and whoever filed them should be charged with wasting police time, even if he is a cop.

fxgai: excellent point! You can't ban drones if you are going to make a kite as heavy as a Kei-car!

John-SanJun. 01, 2015 - 02:16PM JST 700 kg, I think it is 70 kg. 700 kg ,That is heavier then a 150 Cesnor The math don,t work out.

If your maths can work out how to build a 13 by 12 metres rigid frame of bamboo that weighs 70kg you need to get on the phone with the JAXA because you'll take us to Mars! :D

This is just the quick maths L = (1/2) d v2 s CL x (13x12)B = 70.372kg

Just looked at the photo montage and it looks like they screwed up big time! In the past that area was all roped off and only event organizers could enter that area. In fact they even roped off a nearby bridge during the big kite event. I wonder why they changed it this year.

If it was only 70kg and 156sqm (12m x 13m) it would only be as thick as 7 sheets of regular paper, let alone any bamboo.

70,000g/156/7=64.1 (1sqm of office paper is 65g per sqm)

For those who live in the Tokyo, you can go see these kites flown in Zama City in the Kanagawa Prefecture. I go there almost every year. I do keep an eye for them because the wind is very unpredictable, and they do drop like a rock (there are many crashes). Whenever the kite begins to fly over the crowd, I always stand up and try locate a route to run. I was told the kites there were 2,000 lbs. The 700 kg is not a typo.

700 Kg???? C'mon!!!! The Cessna 140 has an empty weight of some 400 Kg. and I'm talking about a light plane including the 85hp engine.. A 700 Kg. bamboo kite is ridiculous.

Here are a couple of videos that I filmed and posted on Youtube two years about the Giant Kite Festival near Zama City. They did have a little trouble with these kites due to lack of the wind, and also too much wind.

https://www.youtube.com/watch?v=iJrnak5Cp4g

https://www.youtube.com/watch?v=XUQSvu_hogw

Also here is a history lesson on the Giant Kites. They have been flying them for over 200 years.

http://www.city.zama.kanagawa.jp/www/contents/1190697106259/

Awesome videos Vernie! Thanks. I love how they are able to bring it in for a relatively controlled landing. They are absolutely massive.

Those spectators didn't just wander into that area, it was a designated viewing area. There were viewing stands right where the kite went down. The "professional negligence" investigation obviously has to do with the organizers allowing the kite handlers to fly their kites over a designated viewing area. Air shows and other events involving aircraft where spectators are present require a 500 foot (152.5 m) buffer between the "crowd line" and where the aircraft will be flying. While kite flying doesn't involve the speeds that planes fly at, there still should be SOME sort of buffer between the crowd line and where the kites might come down.

I saw the footage and its hard to judge the scale of the kite just by pictures, but 700kg seems a bit much. 700kg is like the weight of a kei car.

Going to watch big, heavy kites flying? Stand upwind.

While I thought it was a typo I checked Manipur Today and they also report a 700kg kite falling into the crowd.

http://manipurupdate.com/700-kg-kite-plunges-into-crowd-injuring-4-people/

Cessna 140: 6.55m length, 404kg empty weight, 81kg engine weight, 10m wingspan. Engine a bit more than 10 pct of total empty weight.

If you compared a rolled-up giant kite with a rolled-up Cessna (wings divided into 4 pieces and placed under fuselage), the 13x12m kite's volume would probably exceed the Cessna's, and the rolled-up kite would be relatively solid bamboo and paper compared to the Cessna's mostly hollow tube and wings.

Giant kite closeup: http://wordpress.tokyotimes.org/archives/kite_man_bald02.jpg

Descriptions of various kite festivals, kite weights at the giant kite festivals listed as 880kg (Sagami), 700kg (Yokaichi), 800kg (Showamachi) : http://www.asahi-net.or.jp/~et3m-tkkw/h4.html

With a kite of this size I really don't understand why the viewing area had to be so close. Surely these people could have enjoyed this massive kite in the sky from a safer distance.

VJ,

Cools video's! Clearly these beasts are much more than a handful & in strong winds there is no way they could be controlled, yikes!

Just imagine lifting force needed to send 700kg to 200 metres high. Maybe a category 5 typhoon. Plus how many people to would it take to control it. Just to lift Kite to launch it would take 28 people each lifting 25kg or 14 @ 50kg or 7 @ 100kg and these people are elderly. those who agree it can be done. I would like to know how. 700 kg yes BS

Just to lift Kite to launch it would take 28 people each lifting 25kg or 14 @ 50kg or 7 @ 100kg and these people are elderly.

Maybe you should do some research before spouting off. There are teams of people who fly the kites, not all of them are elderly, and the kites are 700kg. Also, there is no lifting about it, the kites fly themselves, that's how kites work. The people simply simply hold the rope to tether the kite to the ground.

John-San: Just imagine lifting force needed to send 700kg to 200 metres high. Maybe a category 5 typhoon. Plus how many people to would it take to control it. Just to lift Kite to launch it would take 28 people each lifting 25kg or 14 @ 50kg or 7 @ 100kg and these people are elderly. those who agree it can be done. I would like to know how. 700 kg yes BS

I don't know why 200m is a factor. It doesn't seem high enough for changes in air density to matter. If the wind is pushing against the kite, as long as it pushes it all the way up to 200m and the ropes keep pulling the kite against the wind, that height shouldn't be a problem, I would think.

This video shows what seems like a lot more than 28 people, launching a giant kite at the same festival, in 2004. Can't tell how many because the line of people goes off the screen, to the right. Given how fast they're running they're probably not that elderly, on average.

https://www.youtube.com/watch?v=hamjYTFQysg

Yokaichi Giant Kite Festival 2004 八日市大凧まつり

And the caption to this photo in the gallery linked to the video) indicates 100 people are pulling the kite. (gallery: http://photoguide.jp/pix/thumbnails.php?album=7 )

http://photoguide.jp/pix/albums/shiga/yokaichi/tako/25_3380.jpg

100 kite pullers

(The caption to another photo in the gallery says "Kite pullers wanted. This booth, next to the giant kite, is where you can apply to pull the kite. Anybody can apply to pull the giant kite. ...")

I actually seen these kites in person in Tokyo. Yes, they ARE the weight of 700 kg and higher. Even though they are held by several people, it is mainly anchored to the ground by a huge construction backhoe because they need something big and mobile to pull the string at full force for launching and control. Anyone complaining the crowd safety needs to consider that this apparatus is at the full mercy of the wind, and it is not an aircraft. It's extremely hard to control, and it can rapidly move in any direction 360°. Even though I was very far from the kites, due to sudden wind changes I found myself under it a few times. You just have to conscious of the dangers and just simply move away from it. There were some people who still remained sitting on their blankets, but I got the hell out of way.

This is the weight and dimensions of Mild steel UNIVERSAL BEAM 150mm X 14.0kg/m x 10 meters = 140 kg so 5 of these beams 10 metres long = 700Kg. Do you knew what a uni beam. This example has two 75 mm wide flange 9mm thick and a 132mm x 6 mm web . This is mild steel so 5 of these 10 meter beams is 700kg. Cover this with a 100kg of paper and fly it. that is your 800 kg Kite.

Just imagine lifting force needed to send 700kg to 200 metres high. Maybe a category 5 typhoon.

Nothing so dramatic as a typhoon. The wings of aircraft have been lifting that weight for over half a century. The wings of the above-mentioned Cessna 150's could lift a maximum certified gross weight of 756 kg off the ground at around 70 knots. If you doubled the wing area of the Cessna 150 while keeping the weight the same, you could conceivably achieve liftoff in about half of that airspeed. Kites are nothing but large wings with the line providing some amount of stability and resistance to keep the air pressure differential between the face and the back of the kite somewhat steady. If you made the surface area of a 1 ton kite big enough, you could get it airborne with only 10 knots of wind.

You can easily extend the airfoil of 150 cessna by extending the flap and changing the degree to 60% which you need to do when landing a 150 cessna but will stall at 50 knots. but the got nothing to do with a kite which is not a air foil but convex shape due to the fact that it is tethered from the centre and verious other points. If you watch the footage this is shown. The wind is pushing the under surface of the kite into a convex shape not a air foil. The reason why the shape of a air foil make lift is that the air underneath the air foil travel a shorter distant compared to the top of the airfoil which the air take longer to travel which cause lift. go and ask a physic teach at you local school if this kite is 700 kg