A320 Inadequate cabin air ventilation?

[Uplinker]

To save fuel, and therefore money; airlines use low airflow from the airconditioning packs whenever they can. Certainly this was SOP in the two main passenger airlines I was employed by.

In one airline; low pack flow was selected with fewer than:
115 pax A320. 140 pax A321. 200 pax A330

In another airline the figures for low pack flow were: 141 pax A320. 168 pax A321.

There are no CO2 monitors that I am aware of in any of the 8 commercial passenger aircraft types I have flown - there is only cabin altitude monitoring, which will produce cautions and warnings, and automatically drop the oxygen masks at certain cabin altitude limits.

On the A330; Mrs Uplinker, who was a purser, would quite often get one or several passengers feeling faint during long-haul flights. Sometimes they would be put on oxygen. When this happened, she realised that if she asked the pilots for high pack flow, the passengers would rapidly reccover. As a pilot, I learned to select high pack flow if a passenger was reported as feeling faint.

I believe - but cannot confirm - that the filters in the airconditioning ducts were not often cleaned or changed. This led to cockpits being very noisy as the air was forced through the partly blocked filters. And no doubt, a lower airflow to the cabin as well.

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