Wednesday, January 11, 2012

An iPad falling from "Space"?



The video above is going viral currently, being posted on many news websites, Facebook pages etcetera. It shows an iPad being dropped from a balloon at a large height (100,000 feet or 30 km (19 miles)): and surviving.

The video was released by the G-Form company, to promote it's "extreme sleeve" protective sleeve for tablets.

A few remarks on this video:

1) it does not drop from "Space" or even remotely near-Space, as is claimed.

The international boundary of space is at 100 km (62.5 miles), while the USA (deviating from the rest of the world) maintains their version of the space boundary at 80 km (50 miles).

Hence, with approximately 30 km altitude the iPad is nowhere near Space when it is dropped from the balloon. In fact, some military aircraft can and did fly at this altitude, for example the Lockheed A-12/SR-71 reconnaissance aircraft. This is the edge of airspace, but nowhere near true space.

2) It doesn't make a particularly hard landing

Analysing the above video carefully, one can note that after some intitial tumbling, the iPad stabilizes its orientation, and from a certain point on "falls" with the flat back towards the ground, level with the horizon. This is probably helped by the rigged cylindrical device on the back (the GPS tracker probably) and the metal rod attached to one end (that also holds the camera). The weight and position of these probably helps to stabilize the contraption.

As a result, the iPad falls with the flat underside towards earth, i.e. maximizing it's airdrag. This slows the iPad's fall, it basically starts to develop some lift and acts like a wing. A good analogue is a falling leaf. It is no longer truely falling: it is rather gliding.

Look at the screenshots below: this shows the stable attitude of the contraption. Look especially at the third screenshot, which shows the iPad just a fraction of a second before ground impact.

As can be seen in picture 3, details of the ground surface (pebbles, plant stems) are not smeared at all in this single frame. Had the iPad hit earth at large speed, there would have been smearing and not this much detail visible in a single frame.

The fact that all this detail is visible and hardly smeared, simply and undeniably points out that the iPad did not hit earth surface with high velocity. It shows that the iPad in reality glided down at relatively low speed, a speed of at best a few meters/second, similar to a parachute drop.

That is hardly a "hard landing" at all! It underlines that the iPad is gliding down gently, rather than making a true impact. The conspicuous lack of an impact pit is also a sign.

It should be noted that the final part of the video with the landing appears to be sped-up, compressing a longer timespan in just a few seconds. Look for example at the fast movement of the aircraft contrail in the sky just after landing.  This speeding-up of the video aids to give the impression of a "hard" landing, while in reality it was a quite gentle landing.

So: this video is not entirely what it purports to be. Yes, the iPad makes an impressive drop from a high altitude (but not from "near-Space" or "Space"). But no, it does not survive solely because of the protective sleeve. The truth is, that the iPad does not land with high speed at all.





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