Thursday, September 07, 2006

Rust and the Ambulances

Many people apparently think that the rust shown in the pictures of the infamous ambulance incident is proof that the damage is older than 23rd of July 06. As I will show with this posting, this is not quite the case.
I chose to ask people making their living with corrosion protection, and thus knowing a bit more about the matter than an average person who repaired maybe some cars in their live and thus has very limited knowledge. So far I got 3 answers, each one saying that such rusting is quite possible.

"Flash Rusting" actually is a well know phenomenon, this is what some sources on the web say:

Website dealing with Restoration of Camaros:
This will smoothe out the surface and prepare it for the first coat of metal primer. To prevent flash rust, it is best to prime ASAP after stripping, as bare metal will flash rust overnight.

Paper about ship hull cleaning:
A water-blasted bare steel surface will rapidly be covered by so-called "flash rust." Hull areas celaned to an SA-2 or SA-2.5 finish during SERVOJET trials at Tracor Marine showed this red layer of oxidation within a few hours of exposure to the humid Florida environment.

A guide to vacuum coating processing:
For example, if dry, cleaned tool steel is exposed to air, a "flash rust" will form that will prevent good adhesion of a deposited coating.

Report about the restoration of a old steam engine:
The workmanship was of such good quality and that there was little corrosion on the shaft but flash rusting began as soon as the surfaces were exposed.

Conclusion: As can be seen, bare metal/metal alloy surfaces can indeed rust very quickly. The phenomenon is widely known as "flash rust" and is a problem to many people restorating or repainting cars or machinery. Of course, this blog entry is no "proof" that the ambulances were damaged on 23 July, but it pretty much debunks the statements of people saying that there is no way it was damaged that date because of the rust.

Saturday, September 02, 2006

Attack on Ambulances on July 13th

Many blogs and websites suggest that the now infamous damage to ambulances said to be inflicted on July 23th couldn´t have been inflicted by israeli weapons. Examples are:
Riehl World View
Honest Reporting

With this posting, I want to show that weapons used by israel are indeed capable of inflicting the observed damage.
First off, media reports are contradictory and often talk about "missiles" hitting the cars. I strongly advise everyone to take these media and eyewitness reports with some huge grains of salt, due to the following reasons:
  1. Reporters and people interviewed by them often don´t have a clue when it comes to military hardware. Decoy flares are commonly referred to as"missiles", howitzers are "tanks", I could go on and on. For the media "missile" commonly means "something flying through the air".
  2. Difficulties with translation and communication easily change the original meaning of what was said.
  3. Reporters or witnesses might be biased, so tell a "colored" version of the truth.
  4. Being under fire is tremendous stress for the witnesses, leading to conflicting and contradictory reports by them.

That being said, it was reported that the ambulances were under attack and apparently both hit by "something". This "something" apparently exploded slightly outside the ambulances, blowing away their ventilation cover, bending the roof inwards and peppering the roof with shrapnel. Also, a stretcher inside seems to have been slightly torched.
All this is consistent with a single hit by a M789 HEDP round fired by the AH-64 Apache´s M230 chain gun. This is a High Explosive Dual Purpose round containing a small shaped charge for armor penetration, as well as a fragmentation jacket for effectiveness against "soft targets" (hence the "dual purpose" designation).
This explains the damage to the ambulance:
  • due to the operating principle of the shaped charge, the fuze is triggered as soon as a solid object is hit, otherwise the liner would be crushed and penetration would be minimal.
  • blast effect bent the roof of the ambulance inwards, while fragments generated the small holes in it.
  • The stretcher inside the ambulance was hit by the shaped charge´s "jet", the sole part of the projectile effectively penetrating the roof (apart from some fragments) , as designed.

Look at the following evidence showing that a single HEDP round´s effect is indeed similar to the pattern observed at the ambulances:
  1. Video of an Apache firing on an M113 APC. As can be seen, the rounds do pack some serious punch and blast effect.
  2. Video of an Apache engaging personnel and vehicles in Iraq (warning, graphic content) . Vehicles are hit by numerous rounds, but single round´s effect are in line with the above explanations.
  3. Image1, Image2, Image3 and Image4 showing HEDP´s effect against thin metal targets at least in a wider sense comparable to the metal roof of the ambulances.

Of course, the sole thing that is unusal is the fact that there have been only single hits on both vehicles. While unusual, this might can be attributed to the ROE under which the helicopter operated, it is possible that the crew was to plink suspicious targets with single shots ( the M230 is the least damaging weapon at the Apache´s disposal ) and reengage upon hostile/more suspicous reaction.
Hits nearby the red cross aren´t as surprising as they may seem, it is highly likely that the gunner engaged the ambulances using the Thermal Imaging System in the TADS, for which the red cross is not visible, aiming at the center of the target.

Regarding the rust on the ambulance I borrow the words from Noah Shachtman of Defense Tech:
Finally, a word on rust. There’s been a lot of talk about rust, including comments on several blogs about the Reuters van. Let me assure you that it doesn’t take visible surface rust very long to form in the Lebanese climate. If you look up the weather data for Lebanon for the past few days, you’ll see it’s been hot with 70 - 80% humidity. In that environment, rust can form very fast. This is especially true with metal exposed through battle damage. The missile explosion, or whatever, not only strips off the paint, but also the factory-applied galvanization designed to inhibit rust. With no protection in a hot humid environment, rust can and does form pretty fast – within a day or two easily. Overnight under ideal conditions. If you look at the first video of the van, you don’t see rust, but pictures taken a day or maybe two later show lots of rust.

One has also take into account that the most famous high-res picture clearly showing rust has been taken a about a week after the incident, while the damaged ambulance was parked in front of the red cross station only some hundred meters away from the the salty mediterranean, spraying saltwater vapor onto the car in windy conditions, which extremely accelerates the rusting process.
This fact can be checked by watching the video at Kevin Site´s Page (scroll down to 27th July, ambulance video) and comparing the location of the ambulance there with the famous red cross picture.

Conclusion: While certainly showing an unusual damage pattern, it is indeed possible that israeli helicopter´s weapons have damaged the ambulances. There is not enough information available to give a definitive answer though. Personally, I suspect the ambulances were attacked by the IDF, a sad thing that happens in wars, especially when the enemy uses civilians (and maybe ambulances) as shields the way Hezbollah did. I´d expect the ambulances (and the occupants) to have been much more severed, were it a Hezbollah propaganda coup.