HONG Kong may be forced to turn down an offer by Project Orbis to donate its 33-year-old DC-8 flying eye hospital as a museum piece. The charity decided early this year to donate the plane after its retirement to the people of Hong Kong as a thank you for all their financial help. The aircraft has been with Project Orbis for 11 years and has flown to more than 70 under-privileged countries. ''After a half-year study, we found that the area next to the Hong Kong Art Museum [in Tsim Sha Tsui] would be the only place suitable for the purpose,'' said the charity's public affairs manager, Penny Simpson Giles. But the suggestion was rejected by the Urban Council because of concerns over the safety of the old plane in bad weather. Project Orbis was also told that the aircraft would interfere with the viewing of the sculptures in the nearby Cultural Centre and Space Museum. Now the charity is studying other proposals to retire the plane somewhere outside the territory, but Ms Simpson Giles said a final decision had not been made. The retirement date of the DC-8 has been postponed to next year, instead of November, because of delays in the conversion of a new DC-10 flying hospital. The DC-10, donated by three local people, is also a mobile eye surgery teaching hospital but has a larger capacity for medical officers to hold lectures on board. The classroom in the new DC-10 can accommodate 50 people - three times the capacity of the DC-8 - with live transmission of the surgical procedure from the plane's theatre. ''The new hospital will have a separate biomedical-technical training centre, in which a biomedical engineer can teach medical staff how to maintain and amend their equipment,'' the public affairs manager said. Project Orbis estimates the conversion of the plane into a flying hospital with the latest equipment will cost about $31 million. The funds will come from donors around the world. The charity and the Education Department are jointly organising a poster competition for students from 1,500 primary and secondary schools to raise Hong Kong people's awareness of blindness problem and the work of Project Orbis. Ms Simpson Giles said: ''Hong Kong people are more fortunate because they can enjoy up-to-date medical techniques. But many in the under-privileged countries cannot receive proper treatment due to the high surgery cost and outdated equipment.'' She said three out of four blind people in the world could be cured if they had received prompt and proper medication. All entries in The Gift of Sight competition should be sent to the Education Department through schools by January 31. A shortlist of 50 designs will be displayed at Pacific Place from February 23 to 26, with the final judging being held on the last day of the exhibition. Winners, and the school with the most entries, will receive prizes sponsored by five concerns, including the South China Morning Post Family Bookshop. The overall winning entry will be reproduced and displayed in MTR advertising spaces.