AIRLINES face a crackdown on faulty baggage scales which result in passengers paying more to check-in luggage.

A survey by Trading Standards at Gatwick found that 62 of the airport's 321 scales gave incorrect readings. One unnamed airline registered 10 faulty scales among 18 used.

But research by Times Online also reveals widespread confusion among airlines over recalibrating scales. EasyJet claims it can't, Ryanair says it doesn't and BA only resets scales when opening check-in.

The issue is further clouded by revelations that some airlines, including easyJet and Monarch, pay check-in staff bonuses to collect excess baggage charges from passengers, a practice condemned by Trading Standards.

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The Institute has received dozens of complaints from travellers, including one who said her bag weighed 23kg at the airport and 18kg on her home scales. In some cases this can be up to £7.50 per kg on short-haul flights with low cost airlines, and up to £30 per kg on long-haul flights.

Other travellers have contacted Times Online with similar stories. J Fraser from Lytham St Annes was told by Ryanair at Liverpool that the bag he weighed as 17kg at home recorded 23kg on check-in, while Jay from London said a suitcase he took on a connecting flight registered two different weights at the two check-in desks.

The issue is not limited to Gatwick, with problems also reported at Stansted and other UK airports.

Bruce Treloar, Trading Standards Lead Officer for Holidays and Travel, warned airlines they face a crackdown before the summer holiday season begins. Those who don't comply will be named and shamed.

“We will go back to the airports and get the airlines or ground handling companies to train staff to zero-ise the scales between each customer,” he told Times Online.

Treloar says check-in staff should reset or “zero-ise” the scales between weighings to ensure accuracy. While some of the faulty readings at Gatwick were due to mechnical faults with the scales, he says many were due to human error.

“Electronic scales can become inaccurate over time because of intensive use… low cost airlines are reducing their luggage allowance more and more, so the scales must be accurate.”

Gatwick operator BAA says all airlines can reset scales. A spokeswoman said: “It’s a requirement after each weigh to reset the scales to zero using a button of the sort you get on a telephone keypad. More than 90 per cent of our scales work this way.”

She added that scales need resetting after two or more bags have been placed on them for a multiple weigh. This is done manually be pressing a button labelled "CE/C*".

The reset theory is challenged by easyJet, saying check-in staff have no control over weighing scales. “It is rubbish about scales needing to be manually reset to zero whenever you lift a bag off – there’s no manual re-set button,” an easyJet spokeswoman told Times Online.

She added: “After each passenger is checked in, the screen must be cleared before the next passenger can be processed, there is no way to check in another passenger without clearing this screen. This is not related to the scales, however. It is impossible for a passenger to accumulate excess baggage charges from a previous passenger.”

Ryanair, which operates out of Stansted, says its staff do not reset scales between passengers. A spokesman said: "Airport check-in desks belong to the airport. In every country we fly to, check in desk weighing scales are independently tested and calibrated for the airports by the relevant Government Department.

A Monarch spokeswoman said: "Our handling agent at Gatwick advises that the weighing machine equipment used at check-in is automated so the check-in staff do not manually re-set the scales to zero. If any irregularities are detected this is reported and the equipment is re-tested in line with the Weights and Measures legislation."

Conversely, BA says its staff are trained to re-set the scales as soon as they open a check-in desk, but not between passengers.

Airlines also defended paying staff bonuses for penalising passengers with excess luggage. A Monarch spokeswoman said: "As is standard practice within the airline industry, Monarch does incentivise check-in staff for the difficult task of enforcing the rules on weight allowances and also for the sale of extras such as extra legroom seats."

EasyJet says the incentive is there because otherwise staff would let people fly with excess baggage, but the spokeswoman added: “There is no way staff can fiddle the system because they can’t adjust the scales.”

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