Sunday 9 January 2005

Banda Aceh Logistics Basics

This post is a bit technical, I'm afraid. Hopefully not too much. I'm attempting to explain the kinds of difficulty faced by relief efforts in Indonesia, and without using too many technical terms.

First, here's the situation.

From The Australian :
While Australian army helicopters are delivering food and clothing to refugees in Aceh province, problems on the ground have been delaying aircraft carrying aid into the ruined provincial capital Banda Aceh.

There are reports that the city's airport is barely coping with more than 150 aircraft movements a day.

A Defence Force spokesman said Australian personnel were helping set up an air traffic control centre at the airport in an effort to reduce flight delays in the giant aid operation.

"Four ADF personnel are working with the United States, Singapore and the Indonesian military on that," the spokesman said.

The bottleneck at the city's airport forced Defence Minister Robert Hill to cancel his trip to Banda Aceh.

Senator Hill flew to Sumatra yesterday to visit the 500 Australian defence personnel based in Medan and Banda Aceh who are involved in the relief effort, but called off his visit to Aceh.

"The minister will not be travelling to Banda Aceh because of difficulties on the ground relating to logjams with the relief effort in Banda Aceh," a spokesman for Senator Hill said.
150 movements a day, that means one take-off or landing every 10 minutes, 24/7, all day, every day. Probably more like 1 every 6 minutes in daylight hours, one every 15 minutes at night.

From the SULTAN ISKANDARMUDA Aerodrome Data, there are 2 parallel runways, each about 2500 metres or 8200 ft long. PCN (the pressure the runway can take) is 63. (FCXT is explained here - it means Flexible, Low Subgrade, to 217psi or 1.5 MPa, measured by analysis not experiment).

Anyway...

A Boeing 737 has an ACN - which corresponds to the runway's PCN - of anywhere between 18 and 55, depending on whether it's empty or loaded, and the exact model of 737. For an FCXT surface, a 737-700 has an ACN of 19 empty and 42 loaded, while the larger 737-900 has an ACN of 23 empty and 50 loaded.

The important thing is that whether the ACN is 19, 42, 23 or 50, they're all under the runway's PCN of 63.

A quick look at the 737's takeoff distance shows that while a 737-400 only just fits, all other models have plenty of runway.

That means you can operate any model of 737 whatsoever on that runway till the cows come home (or are struck by the undercarriage).

A 737 freighter can carry about 16 tonnes, and has about 120 cubic metres of volume. Note that a normal passenger 737 can carry between 2.25 and 3.6 tonnes, depending on the model, so if you're taking in people, you won't get much freight in.

If you're bring in water - where 1 cu metre weighs a tonne - then the 737 can bring in perhaps 14,000 litres, after packaging and palletising. Food weighs a lot less, you may be limited by volume rather than weight (consider how large a Cornflakes packet is compared to a soft drink can that weighs the same).

Well, if a 737 is good, what about a 747-400 freighter? That can carry a whopping 115 tonnes. That can land in 2500m, just. Except that its takeoff distance even when empty is probably over 3000m. And its ACN is 22 when empty, but 80 when loaded.

It's just possible that a very lightly loaded 747-400 could use the airfield, assuming there's a strong enough headwind. But 115 tonnes of freight would probably bust the runway on landing, and on takeoff, the 747 might not have enough distance.

Now a C-130 Hercules transport, as used by the USAF and RAAF, has an ACN of no more than 40, even when loaded to maximum takeoff weight, including 25.5 tonnes of cargo. Moreover, it can carry at least 5 (more in some models) military-standard pallettes (for ease of cargo handling), and has a drop-down rear door (no need for special elevator vehicles) , so can be unloaded extra fast with minimal infrastructure.

That's why the 15 USAF, 7 RAAF and 1 RNZAF C-130's in Indonesia are operating as hard as they can. Each one is worth maybe 3 737's in practice.

OK, that's good for seeing how much stuff can get in. What about stuff getting out? If we assume each aircraft coming in carries about 16 tonnes of goods, and that half of that can be distributed by trucks to the local area, that means that each flight in will need 8 tonnes of goods going out. As each helicopter can carry on the order of a tonne, that means there's 8 outgoing helo flights per aircraft coming in.

The "150 aircraft movements" figure, assuming no backlog, would be about 16 planeloads per day incoming (and flying back), and a whopping 128 helicopter sorties, taking-off and landing. In practice, there'd be at least 20 planes incoming, and fewer helo flights. Hence a backlog is inevitable. One more thing - there's loads of assumptions in this calculation, some of which are quite crucial. Up the "local distribution" fraction to 3/4, and you need 2/3 as many helo flights, so more cargo aircraft can get in (assuming they can be unloaded in a reasonable time). On the other hand, the SH-60 helicopters in use by the US can only carry half a tonne. I've assumed other helos with greater capacity (like the Singaporean 10-tonne capacity Chinooks) are doing a reasonable share.

Did I mention that for every hour in the air, a helicopter might need a dozen or more hours maintenance? This is a truly Stakhanovite effort, by all the maintainers, the pilots, the fuellers and unloaders, and by Air Traffic Control.

Air Traffic Control? You see, 1 aircraft movement every 5 minutes is a recipe for pandemonium on a small airfield. The level of planning and co-ordination required is fantastic. From An American Abroad :
Banda Aceh airport remains off limits to private aircraft. The airport is being fully utilized by the United States, Australia, Singapore and Indonesian governments to distribute food aid and conduct all related relief operations. Airspace surrounding all the affected areas is also off limits without any prior authorization. A few NGOs have been given authorization to operate helicopters and assist in relief operations. Authorization can be obtained only by written request at least 72 hours prior to intended move. United Nations Joint Logistics Centre - cargo movement request can be obtained here.
Note that last part : United Nations Joint Logistics Centre. But good luck accessing the website, it's overloaded. Guess how many personnel in that "UN" co-ordination centre are in the US orAustralian Military? At a rough guess, I'd say... All of them. It's joint, all right. US *and* Australian, with able assists from Singapore (whose efforts are unsung and amazingly valuable) and the host country, Indonesia. Still, they're all members of the UN, and if a UN badge keeps the political squabblers, bureaucrats and ignorant media off their backs, it's no big deal.

From the UK Telegraph there's this though :
The Indonesian military agreed to lend three helicopters for the UN to use yesterday. But the mission to assess needs was cancelled due to a lack of paperwork.

When UN officials arrived at the airport they were told they had failed to hand in flight permission forms by 8pm the previous night.

"They were at the airport and I was expecting them to go out," said Mr Elmquist. "We were not informed in advance that it was necessary to fill in these forms."
The UN bureaucracy can't even co-ordinate with the "UN" logistics centre, let alone anyone else. In fact, they wouldn't be able to locate their posteriors even with both hands, a map, a compass, written instructions, a satellite navigation system and a native guide. All of which have been provided to them.

But surely there are some people in the Great Co-Ordinating Sheltered Workshop in New York who know their ACNs, PCNs, and their arses from their elbows? From the UN News Centre :
"There are still many areas that we have not been able to get people to, many areas are still, particularly on the western coast of Sumatra, unreachable by land," Kevin M. Kennedy, the Director of the Coordination and Response Division of the UN Office for the Coordination of Humanitarian Affairs (OCHA), told a news briefing in New York of the Indonesian provinces that officials have dubbed the disaster's "ground zero."

He said that in the coming days the relief operations would be calling on international military assistance to help repair key infrastructure, such as bridges, culverts and roads, to allow delivery of food and assistance in Sumatra and Aceh province.

Mr. Kennedy noted that while helicopters now being used are "absolutely critical" to the operation, they are an expensive way to bring in aid. A Black Hawk helicopter carries about a half ton of food. "Now that's extremely important because it may prevent people from losing their lives : but what we will need are roads that we can drive 20-ton and 10-ton trucks down at a much lower cost and deliver much more assistance," he said.
How true, how true. But how are we to get the 10- and 20-tonne trucks in there? A C-130 can carry a 2.5 tonne truck, that's about all it has room for. More importantly, how are we to get the bulldozers, the diggers, the massive 40-tonne graders, and all the other really heavy roadbuilding paraphenalia there ASAP? There are 2 ways : use a USAF or RAF C-17A transport aircraft (the C-5B and AN-124s can't feasibly operate from the airfield with heavy loads), or by ship. And even the C-17s would have difficulty carrying in the heaviest gear, and likely couldn't carry a grader in on a runway that light. Moving in this infrastructure-building equipment in by air would disrupt, or rather, completely stop, the delivery of such "non-essential luxuries" as food and water that are the only things keeping tens of thousands of people alive.

Guess who's providing the ships? They're on their way, HMAS Kanimbla sailed just the other day for example. The US is providing a helluva lot more. The UN is providing, oh, approximately none. But they're sending out news releases saying that they'll be "calling for" this stuff, probably a few hours before it arrives, so they get the credit.

Please UN, get the Farnarckle out of the way and let people who have the faintest clue what they're doing do their jobs. You're not just unhelpful, you're counter-productive. To use the Australian vernacular, you're not just as useless as tits-on-a-bull, you're a millstone around our neck. Go eat a Canape, and figure out how to get your mitts on a greater proportion of the money. Whatever gets you out of the way. To put it bluntly, Just Go and Co-Ordinate Off.

BTW - to the UN people who are actually doing good work, distributing food from the UN warehouses in Sri Lanka and elsewhere, you guys are excepted. You're one of us.


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