It may help a bit, but as the heater is outside the cowling, it's continuously taking in and trying to heat cold air, while pushing the air that it just warmed out of the cowl. If you can put your buddy heater inside the cowling or engine blanket, it will recirculate the already heated air and result in a much warmer engine. If you were using a heater that could put out a lot more BTUs than that one is capable of, it wouldn't matter so much that it's not recirculating.
GyvAir wrote:It may help a bit, but as the heater is outside the cowling, it's continuously taking in and trying to heat cold air, while pushing the air that it just warmed out of the cowl. If you can put your buddy heater inside the cowling or engine blanket, it will recirculate the already heated air and result in a much warmer engine. If you were using a heater that could put out a lot more BTUs than that one is capable of, it wouldn't matter so much that it's not recirculating.
davecessna wrote:You'd run the risk of burning out the heater, no?
There is a risk with any electrical equipment you put inside the cowling of course, or with any kind of heater outside the aircraft as well, for that matter.
As far as the buddy heater inside burning out, it should have a thermostat control to prevent that.
Some common sense must be employed in choosing where inside the cowl you set it, or mount it, in the case of installation. (Yes, that can be done legally)
I made a similar setup for my aircraft out of some 4" scat tubing and some scrap aluminum. It works fine for the typical -5 to -10 we have here.... but I'm not so sure about the -24 we have now.....
I am cowering inside in spite of an ultra mega high pressure system and CAVU conditions.
Depending on the efficiency of your cowl plugs and/or engine blanket, one buddy heater inside the cowl will maintain your engine at a temperature more than warm enough for damage free starts in temperatures way below what most people care to go flying in.
Preheating time is going to vary greatly of course, depending on OAT, wind, engine size, etc.
I'm not a big fan of putting space heaters in cowls. I had one short out on me a couple months ago.... thank god it was on concrete heating up well pipes and not in a plane. It caught a cotton rag on fire two feet away.
I hear what you're saying. I raised my eyebrows a bit too, when I first encountered the practice. There are millions of them out there though and you don't hear of too many cars burning up from them. Thousands of them being used in aircraft too, I would imagine. I've seen a few aircraft damaged from heaters placed outside the cowls.. haven't seen one hurt by a buddy heater yet. Personally, I've only used the compact and simple 900 watt versions though, never the 1850W ones like the one shown in FMD's picture.
Well, as the aircraft is worth six figures, and you have electricity, why not invest in a tanis system?
You need air flow to allow for the heat to completely heat the engine with this tpye of system to avoid hot spots.These lower wattage heaters may allow you to start the engine alright, but unless the engine is completely warm throughout, you can do more damage than if it was just started cold. It is why the huge air flow in the original herman nelsons (and.clean air as well)
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Tanis heaters are good as well, though not without their own shortcomings. What happens when one or two elements fail? They're more than likely to go unnoticed for some time. Regardless what your heat source is, the quality of your engine blanket and cowls plugs can be the biggest determiner of how evenly the heat is distributed and how warm the engine compartment will be kept. Whatever the system, some trial and error is required to be sure it's working. Don't be afraid to stick your hand in and feel around for areas that aren't being heated properly.
Personally, I like stick-on Alaska pads on the oil pan. Even on floats, in the fall they make a big difference getting things to flow first start of the day.
Here is the Airworthiness Notice dealing with the permanent installation of ceramic heaters in aircraft: http://www.tc.gc.ca/eng/civilaviation/s ... 37-548.htm
In any really cold weather, those heaters can't heat squat. In the elements, it would be a fire hazard (If you look at the manual for most of those heaters, they say not to use below -10 (Or was it -20?). Good idea, if you found a proper heater.
Liquid Charlie wrote:unattended car warmers -- space heaters void the insurance -- not certified no insurance -- that simple
That's funny. In 20 years I have never seen an insurance policy like this. Who do you insure your aircraft with Charlie? Perhaps it's time to switch to Geiko.
I think it depends on the policy. I just looked through two different policies, and neither mention this.
Burn one down and see if they are still your friend - search a little closer -- there is likely a clause about "being legal"
I suspect Lloyds and their underwriters will not pay out if your system is not approved -- the best way to clarify is to ask and see what their reaction to a non STC'd engine heating systems -- the insurance companies have no clue about heating or keeping an engine warm so it can be started -- all the care about is if you are adhearing to the rules and that there is no negligence -- unapproved equipment is negligent in their eyes no matter how practical it is -- it's similar to no one burning Arctic Diesel anymore - did it for years but not anymore --
'
It was when I was at First Air that we received the order to stop using "car warmers" because of the insurance company pulling the plug-so to speak -- the reality is that insurance companies will look for any abnormality so as not to pay out -- especially if you are a "little guy" who they don't want to insure in the first place.
Airworthiness Notices - B037, Edition 1 - 4 April 1997
Installation of Automotive Heaters in Aircraft Engine Compartments
Purpose
The purpose of this notice is to inform the aviation public of the requirements associated with the installations of automotive heaters in aircraft engine compartments.
Background
The installation of automotive type heaters in aircraft engine compartments for the purpose of engine pre-heating has been found useful by many operators in dealing with aircraft exposed to extreme cold weather conditions.
Automotive heaters are not controlled aeronautical products, therefore, it is not the intention of Transport Canada to evaluate and approve such installations as they would normally be regarded as minor modifications. Notwithstanding, the installation of heaters requires certification by an Aircraft Maintenance Engineer (AME) to ensure that such an installation will not adversely effect the airworthiness of the aircraft.
Requirements
Prior to making the required certification, the AME must ensure that:
•The device is installed in such a way that it will not interfere with any control or the powerplant cooling airflow.
•The device is installed in such a way that no deterioration of plastic or rubber hoses, cable insulation etc., will occur as a result of the hot air efflux.
•Provisions are made so that, in the event the heater or any of its parts should become detached, no interference with controls or cooling airflow will result during aircraft operation.
•The method of attachment conforms to standard aeronautical practices as outlined in manufacturers' manuals or FAA A.C. 43-13-1A, etc.
•Provisions are made in the aircraft maintenance program to visually inspect, prior to the first flight of each day when the heater has been in use, items located in close proximity to the heater and that could have been affected by prolonged exposure to hot air efflux.
Should it become evident that, through cursory inspections or other means of verification, the installation fails to meet any of the criteria mentioned above, actions must be taken to rectify the deficiency prior to returning the affected aircraft to service.
Liquid Charlie wrote:
Burn one down and see if they are still your friend - search a little closer -- there is likely a clause about "being legal"
I suspect Lloyds and their underwriters will not pay out if your system is not approved -- the best way to clarify is to ask and see what their reaction to a non STC'd engine heating systems -- the insurance companies have no clue about heating or keeping an engine warm so it can be started -- all the care about is if you are adhearing to the rules and that there is no negligence -- unapproved equipment is negligent in their eyes no matter how practical it is -- it's similar to no one burning Arctic Diesel anymore - did it for years but not anymore --
'
It was when I was at First Air that we received the order to stop using "car warmers" because of the insurance company pulling the plug-so to speak -- the reality is that insurance companies will look for any abnormality so as not to pay out -- especially if you are a "little guy" who they don't want to insure in the first place.
Being STCd is only an issue if it's a permanent modification to the airframe. Usually the insurance policy will say they won't pay out if the plane is unairworthy or loaded beyond gross weight/CG limits. I'm pretty sure putting a space heater under the cowl or in the cockpit isn't going to render the aircraft unairworthy.
It sounds like maybe First Air just had twitchy lawyers or insurance. Having said that, if I had a multi-million dollar piece of equipment I probably wouldn't preheat it with a car warmer either.