Never thought it'd be just too darn hot to fly, then summer came.

[A64Pilot]

1 hour ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

They do, they aren’t an evaporative AKA swamp cooler.

I had one and they do work, but I’m assuming he’s saying there is a point that they just aren’t enough.

My issue with them is they worked best with crushed ice of course, but in about 20 min they absorb heat so well the ice is gone, there is only just so much latent heat in ice. Frozen water jugs, blue ice etc extended the operating time but reduced the cooling, you have to have water in them because of course they pump water through a little radiator and a fan blows over the radiator.

Of course in a normal use 20 min is plenty to get you up in cool air, but I was doing test flights with repetitive landings to make adjustments so we just refilled the thing every landing, maybe every other landing

[A64Pilot]

I did my airplane training in Central Tx in Summer after work, so say 4:30 in the afternoon, which is the hottest part of the day, but I was younger and didn’t have the option to choose, it had to be after work and weekends.

Now because I can choose when I fly, there are times like today when it’s just too windy, it’s not so windy to be unsafe, just too windy to be enjoyable

[EricJ]

1 hour ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

They do.   I use them during our monsoon season here when it's reasonably humid.   They're not quite as effective as in the drier air, but still work fine.

[1980Mooney]

1 hour ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

Yes but it draws the intake air through the cooler chest full of ice and water (soon mainly water).  Look at the pic - only one tube.  There is a grill/open slots in the chest lid.

B-Kool - Home

[EricJ]

10 minutes ago, 1980Mooney said:

Yes but it draws the intake air through the cooler chest full of ice and water (soon mainly water).  Look at the pic - only one tube.  There is a grill/open slots in the chest lid.

B-Kool - Home

Most of the cooling is done through the water-air exchanger.   I use mine with freezer packs and only enough ice to fill in between them, so there's not so much water in it.   Lasts a long time that way.

[1980Mooney]

2 hours ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

 

30 minutes ago, A64Pilot said:

They do, they aren’t an evaporative AKA swamp cooler.

I had one and they do work, but I’m assuming he’s saying there is a point that they just aren’t enough.

My issue with them is they worked best with crushed ice of course, but in about 20 min they absorb heat so well the ice is gone, there is only just so much latent heat in ice. Frozen water jugs, blue ice etc extended the operating time but reduced the cooling, you have to have water in them because of course they pump water through a little radiator and a fan blows over the radiator.

Of course in a normal use 20 min is plenty to get you up in cool air, but I was doing test flights with repetitive landings to make adjustments so we just refilled the thing every landing, maybe every other landing

 

14 minutes ago, EricJ said:

They do.   I use them during our monsoon season here when it's reasonably humid.   They're not quite as effective as in the drier air, but still work fine.

To keep it cheap and simple they put the heat exchanger coil inside the cooler chest.  The blower is mounted in the top of the chest and they suck air into the  cooler lid across the heat exchanger into the damp cooler chest.  It works a bit for a while but as the ice melts you are just mainly sucking air through a damp box of 100% humidity.  The humidity is dumped into the plane.  In Houston it just makes it more awful.

To be more effective the heat exchanger and fan should be outside the cooler filled with ice.  Of course it would be more bulky and expensive. 

[1980Mooney]

1 minute ago, EricJ said:

Most of the cooling is done through the water-air exchanger.   I use mine with freezer packs and only enough ice to fill in between them, so there's not so much water in it.   Lasts a long time that way.

I tried that in Houston.  I actually experienced less cooling capacity with the cooler pack approach

[N201MKTurbo]

We have had this discussion before. The most efficient medium is super cooled water ice.

[Skates97]

45 minutes ago, 1980Mooney said:

 

 

To keep it cheap and simple they put the heat exchanger coil inside the cooler chest.  The blower is mounted in the top of the chest and they suck air into the  cooler lid across the heat exchanger into the damp cooler chest.  It works a bit for a while but as the ice melts you are just mainly sucking air through a damp box of 100% humidity.  The humidity is dumped into the plane.  In Houston it just makes it more awful.

To be more effective the heat exchanger and fan should be outside the cooler filled with ice.  Of course it would be more bulky and expensive. 

I made a home built one that pulls the air across the radiator and through a manifold, the air never comes in contact with the water. It does a good job, even leaving Phoenix when it's 100°+.

https://intothesky.com/homemade-ac/

[EricJ]

44 minutes ago, Skates97 said:

I made a home built one that pulls the air across the radiator and through a manifold, the air never comes in contact with the water. It does a good job, even leaving Phoenix when it's 100°+.

https://intothesky.com/homemade-ac/

Phoenix is where it usually matters least, but, yes, for those who think it does matter, it wouldn't be tough to modify a B-kool to do the same thing, i.e., keep the air that flows through the exchanger separated from the chilling ice/water/whatever.

That said, usually when I'm done flying I dump a lot of ice and/or water out of the B-Kool.   I don't think much of it goes into the air, even here when it's dry.

[Pinecone]

23 hours ago, MikeOH said:

( was not night current)

You only need currency to carry passengers.

[MikeOH]

2 minutes ago, Pinecone said:

You only need currency to carry passengers.

True dat… allow me to rephrase, I was not night proficient

[Pinecone]

4 hours ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

They do.  They work fine in high humidity.  Of course, they can lower the temp to the dew point and you get some fog, but it will also lower the humidity in the plane by condensing it on the coil.

[1980Mooney]

7 hours ago, Fly Boomer said:

I thought those things worked like an air-to-water or air-to-ice heat exchanger?

We have a number of pilots remarking that the B-Kool works "fine", "lasts a long time", "drops the dew point".  Yes it will work well initiially and yes it will work better in moderate heat and low relative humidity where the cooling load is less.  But you have to be realistic.

• The B-Kool holds 20 lbs of ice. (also noted on web site)
• One (1) pound of ice absorbs 144 BTU's when it melts
• The B-Kool will provide 2,880 BTU's of cooling from melting all the ice
• You can probably get another 200 BTU's of cooling as the fully melted water rises from 32 degrees to 42 degrees F.
• So fully exhausted a B-Kool provides a whopping 3,000 BTU's cooling in total
• A typical small car air conditioner will provide 12,000-18,000 BTU/Hr cooling.  A large car air conditioner provides 24,000-40,000 BTU/Hr cooling

So the B-Kool in total will provide the equivalent of what a small car A/C can to in 10-15 minutes on high.  If you are taxiing and holding for 10 minutes on a blistering Texas Gulf Coast day, the B-Kool will largely be spent.  Then the water in the chest will start to warm up and instead of condensing on the coils, it will act as a humidifier.  

It works but just don't get your expectations too high.  

[EricJ]

29 minutes ago, 1980Mooney said:

It works but just don't get your expectations too high.  

You won't freeze a side of beef with it, but I used it regularly during my intrument training, doing constant approaches in ~110F for a few hours at a time, and it worked fine through all that.   I've never needed it do more than that and usually a lot less.   You really just need it on the ground and when you're low, which typically isn't that long.

Sounds like it's not for you, though.

I did my multi-engine training, also during the Phoenix summer for some reason, in a brand-new Seminole with factory a/c.   My B-Kool was better.  Seriously.   I was surprised.

Anyway, a lot of people in AZ use them or the various equivalents like what Skates made, but our application isn't typical.   

[Utah20Gflyer]

On a hot day (90-100 Fahrenheit) in Utah I find the B cool lasts about an hour, maybe slightly longer. It has a hard time keeping up especially if the cabin is heat soaked.  It does take the edge off a bit, but it’s definitely not Air conditioning.  
 

I am looking at making some duct to go from my SUV to the plane so I can use the vehicles AC to thoroughly cool the cabin while I preflight the plane.   I have no idea whether this will work or not.  

[EricJ]

16 minutes ago, Utah20Gflyer said:

On a hot day (90-100 Fahrenheit) in Utah I find the B cool lasts about an hour, maybe slightly longer. It has a hard time keeping up especially if the cabin is heat soaked.  It does take the edge off a bit, but it’s definitely not Air conditioning.  

I am looking at making some duct to go from my SUV to the plane so I can use the vehicles AC to thoroughly cool the cabin while I preflight the plane.   I have no idea whether this will work or not.  

Are you using ice or freeze packs or some combination?    General experience seems to be that freezer packs last longer, which has been my experience as well. 

 

[Justin Schmidt]

IcyBreeze works wonders, put it in during preflight...nice and cool. Runs off of its own battery pack

[1980Mooney]

3 hours ago, Utah20Gflyer said:

On a hot day (90-100 Fahrenheit) in Utah I find the B cool lasts about an hour, maybe slightly longer. It has a hard time keeping up especially if the cabin is heat soaked.  It does take the edge off a bit, but it’s definitely not Air conditioning.  
 

I am looking at making some duct to go from my SUV to the plane so I can use the vehicles AC to thoroughly cool the cabin while I preflight the plane.   I have no idea whether this will work or not.  

On a hot summer day in Houston the B Cool lasts about half an hour.  This is just basic physics and a function of relative humidity.  The "latent heat" load in any cooling system is directly related to the humidity of the air. The Latent heat is the heat capacity of the water vapor.   And the latent heat cooling load can be more than the "sensible heat" cooling load.

In the summer, the average relative humidity is:

Utah around Salt Lake City - about 40% 

Phoenix -  about 20-30 % average 

Houston - about 70% 

In Phoenix there is little to no Latent Heat load - so the B Cool works at its best.  It's 3,000 BTU's are cooling the dry air - almost all sensible heat.

In Utah the Latent Heat load is about 60% more than the sensible heat load.  Only 63% or 1,890 BTU of the 3,000 BTU's are cooling the sensible heat (the sensible temperature).  The other 37% or 1,190 BTU are consumed in the heat capacity of the water vapor.

In Houston the Latent heat load is about 1.9X more (190%) than the sensible heat load.  only 35% or 1,050 BTU of the 3,000 BTU's are cooling the sensible heat (the sensible temperature).  The other 65% or 1,950 BTU's of the the total 3,000 BTU's are consumed in the heat capacity of the water vapor.

Of course the B Cool works better in Phoenix and of course it delivers much less sensible cooling capacity in Houston.

Example 5000 SCFM Air Conditioner - Required Cooling Load vs Relative Humidity

 

That is Latent Load as a % of Total.

Edited June 21, 2023 by 1980Mooney

[Fly Boomer]

9 hours ago, Utah20Gflyer said:

On a hot day (90-100 Fahrenheit) in Utah I find the B cool lasts about an hour, maybe slightly longer. It has a hard time keeping up especially if the cabin is heat soaked.  It does take the edge off a bit, but it’s definitely not Air conditioning.  
 

I am looking at making some duct to go from my SUV to the plane so I can use the vehicles AC to thoroughly cool the cabin while I preflight the plane.   I have no idea whether this will work or not.  

This sounds excellent!  Cars typically have huge cooling capacity -- an SUV even more.  If you build something, let us know how you did it, and how it works.

[N201MKTurbo]

Quite a few people at the airport have rigged up window air conditioners for their planes. They mostly use it for working on the plane. They get some flexible ducts and duct tape and rig it up. I was working in a PA-32 that was uncomfortably cold inside.

[N201MKTurbo]

But most people just suck it up and go fly. Altitude is your friend. A friend of mine always says right after takeoff "Climb and maintain 70 degrees"

[A64Pilot]

1 hour ago, Fly Boomer said:

This sounds excellent!  Cars typically have huge cooling capacity -- an SUV even more.  If you build something, let us know how you did it, and how it works.

Where I worked building crop dusters we had to work inside of the hopper, a fiberglass tank without much airflow in South Ga. In Summer it was tough.

I got a decent sized window unit AC, put it on a rolling table and had a sheet metal duct cobbled up to fit over its air discharge that hooked to a plastic hose we had, but a drier duct would work just as well, put the hose in the hopper and they could work in the cool, the biggest hose you can find the better, maybe a short piece of flexible HVAC duct would be best.

I’m sure it would work to pre-cool an airplane in a hangar, pre-cooling is the key, even without any cooling if it’s cool to start with and taxi times isn’t long it won’t ever get real hot inside, but if you have cooling, like a Bcool for example it will stay cool, knocking down the initial heat load is what’s hard, if you start cool the amount of energy to maintain that is a fraction of what it takes to cool initially.

5,000 BTU AC’s are less than $150 and if you shop around you can even beat $100

Oh, and vent “booster” fans are widely available that would boost the airflow through the duct

On edit, If I ever install an AC, I want it to be an electric one, just so that I could plug in the airplane and run it until the inside of the airplane is nice and chilly, then push it out of the hangar

Edited June 21, 2023 by A64Pilot

[Skates97]

After a few posts talking about humidity and everything not working equally in different parts of the country, I will preface this by saying I get it. However, here is an example of how my homemade  AC worked this past weekend which I think is similar to what you could expect from a B-Cool unit.

We were in Phoenix for Father's Day weekend to visit my folks and parked at KIWA. The plane sat on the ramp Saturday and Sunday soaking up the 100°+ heat. Sunday's high was 104° and it was still 101° outside when I was doing preflight on the plane at 4:30pm. The cooler had been in the plane the entire time so it was a nice toasty 100°+ when I added the ice. I put 21lbs of ice in it (three 7lb bags of cubes because nobody was selling blocks) along with about 1 1/2 gallons of water to circulate through the system. 

It was a quiet day (shocker) with the only other traffic a 737 that had just landed and some poor soul flying a UND plane so there was no delay for taxi or departure. It wasn't making the cabin cool, but we did have cool air blowing on our shoulders, back of the neck and back of the head which does wonders for keeping the body cool. I was sweating when we got in the plane but by the time we were airborne just after 5pm I was comfortable.

We climbed to 5,500' to stay under the Bravo shelf where it was 80° OAT and were stuck there for I think about 10 minutes or so, then continued the climb up to 10,500' where it was a nice 52° OAT. It was still blowing cool air when we got to cruise altitude about 35 minutes after departure. Somewhere along the way during the rest of the flight the ice was done, but it was still nice to have the air blowing on your back.

It made a huge difference in the comfort level of the flight, especially for my wife which is more important than my comfort, although it does contribute to my overall comfort... 

[bcg]

My daughter and I flew from F37 to ERV Sunday. When we got to ERV, it was 105°, I turned on my B Kool at about 7500 and it kept it comfortable in the cockpit. Yeah, it could have been a few degrees cooler but, we weren't sweating.

I do mine a little differently, I put just enough ice water in it to circulate through the pump and then add freezer packs and frozen water bottles to fill it the rest of the way. I have the water dump on top of the frozen water bottles so it runs down it to cool off before being pumped again. Since we had 55° at 11,500 and the cabin was cool, I would rather have a longer duration of cool air that keeps us comfortable than a short duration of ice cold air. We ran it for about an hour through our descent, landing and taxi and the water bottles were still cold enough that they were pleasant to drink.

The biggest thing is to not let the cabin get super hot to begin with. I don't have a hangar but I do keep my plane covered, which makes a big difference. I also just added the cling tint, which I think will help as well. I do what I can if the pre-flight before removing the cover and get the B-Kool running once I do. If I can get 30 minutes from it on the ground and another 45 - 60 when we land, it covers the critical heat.

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