B737-200 Gasper fan airborne operation?

[Centaurus]

The purpose of the gasper fan installed in the 737-200 is to provide boosted cold air through the gasper fan outlets during ground operations or low airflow in flight. That being so, there would appear to be no operational need for the gasper fan to be operated while the aircraft is airborne. Over the years since the introduction of the 737-100/200 some operators leave the gasper fan on for all operations below 10,000 ft. It seems to me that this is unnecessary given that both packs supply sufficient cooling airborne to cater for a comfortable cabin temperature.

Moreover, if the cabin temperature is comfortable during cruise and descent, there is nothing to be gained by switching on the gasper fan at 10,000 ft (for example) on descent because all it does is to pour cold air on to the passengers when the cabin is already stabilised at a comfortable temperature. If the gasper fan is needed for ground operation it can be switched on during the taxi in checks or switched off after take off as part of the after take off checks instead of being left until 10,000 ft.

The relevant Boeing manuals do not address gasper fan policy except to say the gasper fan outlets should be open for hot weather operation on the ground. Your comments would be appreciated.

[777AV8R]

In over 8000 hrs on the 100-200, I never did turn it off. The pack flow on the ground was never enough to make it comfortable for a full load of passengers. The same is true airborne especially during turbulance. It was always good to keep the cool air on pax if they wanted it to keep from getting airsick, its a feature that still would be nice to have on some todays newer aircraft. Remember, what might be comfortable for one person may be too hot for someone else, the ability to gently cascade some fresh cool air is nice. If a person is too cool, shut the -eyeball vent off.

Also, the gasper provides extra fresh air on the flight deck. On a hot day it was nice to have...also great for the 'magic show'.

[vapilot2004]

Airflow is sort of like precision in carpentry. Measure too long - just make another cut. Measure too short and it's time for another board. :)

777AV8R has got it - provide lots of air.

Even with newer 737 designs in Auto, at least one recirculating fan still operates unless both packs are on high while airborne.

[Fargoo]

also great for the 'magic show'

The incredible floating lightbulb? :ok:

[A37575]

But the recirculating fans are not the same design reason as the gasper fan in the 737-200. I would have thought if passengers needed to have a blast of cold air on their faces airborne, the crew up front might just have the wrong temperature selected on the air conditioning controls?

[Swedish Steve]

A few years ago we had a lady passenger board a B757. Sit down and reach up to adjust the gasper air flow. When she found that they were not fitted, she stood up and got off again!(It was an option on B757. Some have, some haven't)