A GROUP of academics has launched a signature campaign in the tertiary education sector in protest against the proposed old age pension scheme. They are calling on the Government to scrap the proposal which they describe as ''unfair and not feasible''. Academics from the University of Science and Technology, Hong Kong University, Chinese University, Hong Kong Polytechnic, City Polytechnic and Hong Kong Baptist College have joined the campaign. They are telephoning personal and business contacts rather than setting up a counter to solicit signatures. Dr Francis Lui Ting-ming, acting head of the Department of Economics, University of Science and Technology, who initiated the campaign, said they had a duty to make the public aware of their arguments. ''Academics seldom play such a high profile [role]. I know this is very unusual. But we believe we have the responsibility to explain [our arguments] to the public,'' Dr Lui said. Their campaign will finish at the end of the month after signatures are collected and a statement drafted for publication. The pension scheme, unveiled by the Deputy Secretary for Education and Manpower, Lam Woon-kwong, last month, requires employees and employers each to contribute 1.5 per cent of workers' salaries to the fund every month. In return, a person aged 65 or above would get $2,300 (at 1994 rates) a month. Dr Lui condemned the scheme as not feasible. He doubted whether there would be enough working adults to contribute to the fund and pay for the elderly whose number would increase substantially in the next 20 to 30 years. ''At present about 46 per cent of the population are aged between 20 and 45. These people will retire and rely on the pension scheme. ''But there will not be enough working adults to support the elderly because of low birth and mortality rates. Hong Kong has the third lowest fertility rate and the second longest life expectancy in the world,'' Dr Lui said. He said the Government would have to rely on emigrants for contributions and this would create housing and welfare problems. Dr Lui and the other academics participating in the signature campaign said the Government should instead make saving compulsory for every working adult. The savings could be kept in a government fund generating interest or could be partly withdrawn for private investment to obtain a higher return and diversify risk. They said compulsory saving would be better than the proposed old age pension scheme as people would get benefits proportional to their contribution. But not all academics were against the scheme. Tsang Shui-ki, senior lecturer of Baptist College's Department of Economics, said the Government's proposal used a ''pay-as-you-go'' mechanism which would benefit the elderly immediately. Sammy Chiu Wai-sang, senior lecturer at Baptist College's Department of Social Work, said the Government's proposal was manageable and comprehensive enough to cover full-time workers, part-time workers and housewives, who he believed should also be protected. He said the contribution rate was moderate and acceptable. A social work lecturer from Hong Kong University, Nelson Chow Wing-sun, described the scheme as unjust because people who contributed more would not get more in return.