Forum: F-16 Procedures

Hi all,

I understand that the hot light will come on when my in-flow is less than 64% or when the temperature rises above 165 for a period. My question are as follows:

1) What is the so-called in-flow refering to? my ECS output or the -60 output?
2) What can make my light comes on? Other than those I mentioned
3) Is there any way to make it go off and come on? sort of an ops chk for the caution light?

I tried going thru the GS,STM but I still can't find my answers. Please advise... any small clues to the answer may be useful.

Thanks.

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Any one knows the ans? Hope someone out there can help me out this time... I'll await your answers. thanks

The equipment hot light comes on because of a simulation in the electronic equipment cooling control box. The box is fastned to a cooling pipe in the nose behind the flight control computer. Air is taken from the pipe and flows past a small heaterelement with a fixed strength. The air is heated and passes to 3 temperature sensors. One controls the cooling valve and the priority valve, one lights the EQUIP HOT light and one shuts off the heater so the box doesn't burn is self.

A simple way to check if the box works is to turn on the power. It should come on within 10 ot 60 seconds, I seem to remember.

Snags that cause an equipment hot warning include stuck cooling turbine, bad 13. stage valve, defog handle top far back (if you don't have a priority valve).

Hope this helps

Thanks for the reply pal...I guess you've just increased my knowledge.

Newbie Joined: Jan 15, 2007 - 04:29 AM Posts: 8

Usually when the equip hot light comes on, with engine running there is a lot less air coming out of the ECS exhaust in the left MLG and the ECS inlet doors are open about half the normal. Many times it's the turbine either going bad or a valve not controlling the bleed air right. Try hitting the panel covering the turbine with a chock - might help narrow the search!

The T.O. specifically says not to hit the turbine while in operation as it my shell out. The easiest way I have found to see if turbine is working is to feel the duct coming right off of the turbine. It is covered in the insulation and if it is hot you got stuck turbine.

Newbie Joined: Jan 15, 2007 - 04:29 AM Posts: 8

Well hell, if you hit the panel and the damn thing shells out, good on you - you just the culprit - a bad turbine! Gotta love those TO's!

Enthusiast Joined: Jan 28, 2006 - 10:52 AM Posts: 57

MF, the air coming out of the LMLG has nothing to do with the turbine not working or the blow in doors half way open....... That air comes straight off the motor to the ejector valve..............

FYI - If there is extremely high ground humidity at the operating location of your F-16, the light may come on when it is saturated by condensation. I've seen numerous aborts for "Equipment-Hot" in locations like this. Confused

When the pilot jumps into the jet dying of heat and soaking with sweat, they will naturally go full-cold with the air control. This causes all the moisture inside the cockpit to condense when it is cooled rapidly. This in turn saturates the associated ducting, and electronics/sensors. Then you would get an abort for equipment hot during pre-flight, or just after launch. Mad

To solve the problem the pilots needed a little briefing from the EE guys, to explain how to "ease" into the cool air and let the system handle it in a more controlled way This allows the massive mount of moisture to be processed in a way that it drains, and not collect in the electrical components. Problem mitigated! Cool

(The sensor we're talking about here was actually dripping with water when removed for replacement!) Shocked

Hope this helps others in High Temp/Humidity areas (we know where that is)... Thumb

Enthusiast Joined: Jan 28, 2006 - 10:52 AM Posts: 57

The air that goes to the equipment is always full cold!!!!! I am an E/E guy/instructor.

Just because the turbine "shells" out does not mean that it was bad. So I guess it is OK to cause further damage to the A/C to determine a bad part.

If there is moisture getting to the equipment I would suggest going to the high humidity "socks" The cloth ones are most likely getting too saturated to do its' part in removing water. The water is removed before the air gets to the valves that control the amount of cold air going to the cabin/avionics. If he is getting the hot light it is due to the lack of air flow not the temperature per se.

If there is a lack of air coming out of the heat exchanger exhaust that is a bleed air problem not a cooling problem. They are 2 different subsystems.

Forum: F-16 Procedures

Equipment hot light