27  Contingent liabilities

In connection with the sale of its products, on some occasions the Group and Company enter into individually and collectively significant long-term contingent obligations. These can involve, inter alia, guaranteeing financing for customers, guaranteeing a proportion of the values of both engine and airframe, entering into leasing transactions, commitments to purchase aircraft and in certain circumstances could involve the Group and Company assuming certain of its customers' entitlements and related borrowing or cash flow obligations until the value of the security can be realised.

At December 31, 2000, having regard to the estimated net realisable value of the relevant security, the net contingent liabilities in respect of financing arrangements on all delivered aircraft amounted to £184m(1999 £118m). Sensitivity calculations are complex, but, for example, if the value of the relevant security was reduced by 20%, a net contingent liability of approximately £347m(1999 £272m) would result. There are also net contingent liabilities in respect of undelivered aircraft but it is not considered practicable to estimate these as deliveries can be many years in the future and the related financing will only be put in place at the appropriate time.

At the date these accounts are approved, the directors regard the possibility that there will be any significant loss arising from these contingencies, which cover a number of customers over a long period of time, as remote. In determining this, and the values above, the directors have taken account of advice, principally from Airclaims Limited, professional aircraft appraisers, who base their calculations on a current and future fair market value basis assuming an arms-length transaction between a willing seller and a willing buyer.

Contingent liabilities exist in respect of guarantees provided by the Group in the ordinary course of business for product delivery, performance and reliability. The Company and some of its subsidiary undertakings have, in the normal course of business, entered into arrangements in respect of export finance, performance bonds, countertrade obligations and minor miscellaneous items. Various Group undertakings are parties to legal actions and claims which arise in the ordinary course of business, some of which are for substantial amounts. As a consequence of the recent insolvency of an insurer, the Group is no longer fully insured against known and potential claims from employees who worked for certain of the Group's UK based businesses for a period prior to the acquisition of those businesses by the Group. While the outcome of some of these matters cannot precisely be foreseen, the directors do not expect any of these arrangements, legal actions or claims, after allowing for provisions already made, to result in significant loss to the Group or Company.

In addition to the guarantees referred to in note 20 at December 31, 2000, there were other Company guarantees in respect of financial obligations of subsidiary undertakings £38m(1999 £4m) and joint ventures £14m(1999 £46m).