Compact GCU
 

In an ideal world what I'd like is a compact and self contained air conditioning unit, probably run off a small APU-scale gas turbine engine and run off AVTUR, then connectable to an aircraft's cabin air, most likely through an external GCU connection.

In a really ideal world. it would be small and light enough to be manhandled into an aircraft hold, and out again at the other end when we have our jet sat for hours on some hot pan in the middle of nowhere and want to keep the cabin temperatures down.

Yes I know, most people will run an APU to run the aircraft's own a/c, but we have reasons for not doing that (specifically a lot of energy intensive kit on the jet that also needs to run on the ground, and the APU hasn't enough grunt to do both). Yes I also know that many people will just hire a GCU, but in many countries that's really not possible, particularly as most operators now will use the APU for cooling.

Does anybody know if this amazing device exists anywhere in the world, and if so where I can get hold of a salesman for one?

What you really want is a fuel cell, which can do the same job as an APU but makes no noise while doing it...

What I really want is a magic wand that just magics about 20kW of heat out of our cabin for 4 hours. Noise I can live with!

Would it be easier to find a a way to power the "other things" so the APU
could deal with a/c?

I realize that there could be certification issues etc on power delivery that might be harder than for external a/c.

We have a lot of power-hungry kit and a small APU so we can only run some of the kit but not all of it, off the APU. Or we can run the A/C - badly off the APU. It starts the engine and runs the flight controls okay, but that's not what we're after.

Current preference is to run the kit off a GPU, and the A/C off the APU but it doesn't really give good enough cooling effect. Most places we go we can't get a GCU - and when we can they're usually heavily in demand, or unreliable, or both. So a compact air-portable external GCU that we'll only use externally and on the ground (so no particularly certification issues) combined with the APU running the aircraft a/c is what we'd like to do. GPUs to run the kit on board is at-least quite easy to rent wherever we are.

But first catch your compact GCU. I'm just hoping that somebody, somewhere, makes such a device and I've just not found it yet.

It is out there and more.... You need to find someone to link you with it.

Stop looking for the equipment, look for the link to the equipment. Maybe someone who has the same needs as you, is comfortable in the grip of any challenge, and can deliver a solution that will charm everyone aboard.

Look in the Mojave desert....

Unless I'm missing something between the lines, I've spent a reasonable amount of quality time in the Mojave desert over the years, and they always use aircraft APUs or sodding-great-heavy-massive ground transportable GCUs.

May be that by splitting the a/c unit from the power supply you will have a better chance of finding off the shelf solutions.

More likely to fit in avaialable space and also might be possible to leave a/c unit in cargo hold while in use.

If you google on "emergency air conditioning" or "industrial portable a/c" or similar you should find leads to manufacturers that can solve the a/c part of the problem.
Once came very close to having to rent one in the middle of winter to cool multiple large computers until we got approval to open a window.
(The window of course was not -designed- to be opened...)

Appropriate generators should be easier to find or power can be from ground sources.

Scaled....

... make aeroplanes.

Thanks and yes - if all else fails, a lightish ACU may be runnable from a locally procured GPU. Not the perfect solution, but possibly the most available.

And spacecraft, which need to be cooled.

At the very least, you would be talking to an engineer, who is fluent in the field you have requested to access.

Stay cool :ok:

Interesting point.

I've been there once recently, but they're not a company with a great love of talking to outside people about how their technology works!

Understandably so, most billionaires are sensitive about their money, and the value of their proprietary kit.

The best way to get a foothold on the path to success is to inquire the cost of doing so.

Not paying the cost, but asking the price. Wear the 'client's coat', and ask some sincere questions......

Most 'estimates' are provided gratis, and contain some valuable data that may invigorate a solution. These are pilots, like you, and are interested in your challenge.

imo

It's called a tent... Just erect a shady shelter over fuselage and wings... :cool:

So basically nobody knows of anything then.

Re: tent. Disregarding the 45x60m footprint of the aeroplane, the real problem is that most of the heat is generated inside the aeroplane. Sun's a mild nuisance, but only a mild one.

Why not use the readily available portable airconditioning units that are used for conventions etc? They run off mains power, so you would need either a genset or park close to a hangar and use ground power, but they'd easily do the job.
Just run the cooling duct through a cockpit window and you're done.

I've got an external A/C input mod on the jet so don't need to run it through a window, but what I don't have is any certainty of which airport we'll be operating from day-to-day. Hence wanting air-portability.