General conditions of sale


By clicking the box ‘I unconditionally accept the general sales terms and conditions’, the Client attests having read, understood and accepted all general terms and conditions described herein.

The purchasing process cannot proceed further without clicking this box.

The current general sales terms and conditions exclusively govern all contractual relations between Optimal Aircraft Design (hereafter referred to as OAD), 31 rue de l'Yser, 5020 Namur, Belgium and the Client. The Client’s general or specific terms and conditions cannot be imposed on OAD. Only specific terms and conditions indicated in the Agreement purchase order, other contract or agreed to in writing by parties concerned can operate as a waiver to this provision.

Current general sales terms and conditions will also be automatically emailed to the Client with order confirmation.

Depending on context and unless otherwise specified, (i) the term ‘Client’ used in the current terms and conditions must be regarded as meaning any prospective customer, purchaser, licensee/license holder, distributor or dealer, whether an individual, consumer or professional; (ii) the term ‘Contract’ as meaning an offer, quote, purchase order, licensing agreement, distribution contract, maintenance contract, assistance services contract or any other contract agreed to between parties concerned whether finalised via the OAD website ( - or directly with OAD; (iii) the term ‘Product’ as meaning any license to use the OAD aircraft design software programme and/or maintenance of said design programme, programmes, software, platforms, formulas, services, modules or systems developed and/or commercialised by OAD.


The Client attests full legal capacity and to being of legal age to enter into a binding contract with OAD.


The placing of an order by the Client can only be considered valid and the Contract entered into once the Client has fully completed the ADS site purchasing process and finalised payment of all sums due.


Should the Client purchase a Product within the context of professional activity, he/she does not have the right to renounce his/her order.

Should the Client purchase a Product for private purposes then he/she is considered a ‘consumer’ and has a time limit of seven (7) working days to withdraw from the contract without penalty and without stating a reason. The cost of shipping goods back to OAD must however be borne by the Client.
The time limit of 7 days runs from the day after delivery of the CD Rom incorporating the Product to the consumer Client. Unwanted Products must be returned new, unused and complete, in original (unopened and untorn) packaging and in original condition along with any accompanying items (mainly instructions for use and original documentation in packaging) to OAD’s address. If conditions in this paragraph are complied with then OAD engages to reimburse the consumer Client within thirty (30) days from package receipt date at OAD all monies paid as well as the cost of the outbound shipping costs. However return shipping costs remain the responsibility of the consumer Client.
Moreover, should the consumer Client have opened or torn the CD-ROM packaging label or used the Product, he/she forfeits any renunciation rights.
Updates and upgrades downloaded from the OAD website ( - cannot be surrendered as the service is delivered directly upon ordering prior to the 7-day expiry period.


The Product is delivered to the Client in CD Rom format in sealed packaging. The Client is required to install the Product him/herself in strict compliance with instructions in the User’s Guide delivered with the CD Rom.

The Client does not acquire ownership rights of the Product, instead he/she has, as a personal right, a non-exclusive and non-transferable license to use the Product for an unspecified duration and, if needs be, access to future versions, upgrades and updates if said Client has purchased a maintenance contract. The number of licenses will be equivalent to the number of simultaneous users who will be using the Product on the Client’s computers. The price paid includes a license fee for the Product.

Updates and upgrades need to be downloaded by the Client from the OAD website ( -


Prices are excluding VAT and other taxes, custom fees, and any other taxes imposed on or with respect to purchased goods that are not specifically mentioned in the Contract, and are EXW (ex-works/factory).

Prices are in Euros and must be paid in this currency.

Payment must be made via the Ogone payment gateway when placing the order. OAD accepts no responsibility whatsoever for the online payment process. Payment is directly managed by Ogone ( and no information relating to the payment process is transmitted to OAD.

The Client will automatically receive an email to confirm whether the payment process has been successful or not.


Unless stipulated otherwise, the CD ROM of the Product will be delivered within 30 days of payment at the latest.

Updates and upgrades will be immediately accessible from the OAD website ( - as soon as payment has been successfully processed.

Delivery times are not of the essence of the Contract. OAD can only be held responsible if the delay is significant and exclusively attributable to gross negligence or intentional fault on its part. The Client has no right whatsoever to decline the Product, demand compensation or cancellation of the Contract as a result of delays in delivery that are not OAD’s fault.

Any subsequent changes requested by the Client that are not in compliance with the initial agreement will generate surcharges and could push back the delivery date.


The Product is designed and developed within technical feasibility constraints and complies with EU standards and with precise specifications outlined in the Contract. However, OAD retains the right to change some features of the Product as long as applications are not modified and performance is not impacted negatively in the process.

Once the Product has been delivered to the Client, the latter will need to install and comprehensively test it within eight (8) calendar days and inform OAD in writing in a precise and detailed manner of any defects or non-conformity. Once this time limit of eight days has passed, the Client has no remedy. The Client can under no circumstances refuse to accept the Product on the grounds of minor or futile reasons. OAD’s responsibility is strictly limited to taking any adequate measures deemed useful or necessary to correct or repair defects within a reasonable time frame.

The Product has been designed so that anyone can install and use the Product as long as they carefully follow all the recommended instructions provided in the Product User’s guide. OAD cannot be held responsible for the inability of the Client to use the Product. Under no circumstances can the Client cite an inability to use the Product as grounds for non-conformity.

OAD’s after sales service is in principle only contactable by telephone or by email from 9am to 5pm (Belgian working days and hours).


In the event that it its contractual liability is engaged by imperative laws, OAD can only be held liable for direct damages resulting exclusively from its own gross and intentional fault, to the exclusion of all other damages among others incapacity to use the software, loss of profit, increases in general costs, disruption in scheduling, loss of business, revenue/income or anticipated savings, or of any other indirect damages or loss. The total amount of damages for which OAD can be held legally accountable cannot exceed 10% of the Contract total.


All title to the copyright and all other intellectual property rights present and future whatever they may be regarding trademarks, logos, drawings, graphics, formulas, technical approvals, products, concepts, methods, technology, plans, savoir-faire and original ideas aligned to the Products are the exclusive property and remain with OAD, whether or not the latter are legally protected or duly filed. The Client agrees not to copy or replicate the Product in any way whatsoever, nor to commercialise identical or similar systems, nor to record or register any trademark, logo or model belonging to OAD, nor as a general rule establish copyright over any of this OAD material, nor to alter the trademark or decompile the Product he/she has purchased.


Any documentation, manual/guide, software, concept or other information without exception that is passed over to, delivered or shown to the Client or expanded on by whomsoever within the framework of the Contract is considered strictly private and confidential.

Unless this information is already known to the general public within the strict letter of the law, the Client cannot in any way, directly or indirectly, even for an indefinite period following full execution or conclusion of the Contract, (i) reveal or communicate said information to a third party, (ii) nor make use of it, for his/her benefit or for a third party, other than in strict compliance with the Contract’s execution.


All personal information transmitted by the Client to OAD is considered strictly private and confidential.

The Client’s personal information is only used internally by OAD to handle the Client’s order and to enhance and personalise communication between the company and the Client mainly by the sending of information letters or emails that the Client has expressly confirmed that he/she wants to receive when entering into the Contract.

The Client’s private data is kept by OAD and is accessible to the Client who retains the right to change, amend or delete said data. In accordance with the law, the handling of Clients’ personal data is subject to a declaration by the Belgian Commission for the Protection of Privacy. OAD engages never disclose Client details to a third party with the exclusion of any natural or legal person trying to acquire any business assets belonging to OAD, whether in whole or in part.


Should the Client be a commercial business, OAD is authorised to quote the name of the Client as a reference on any supporting material it deems appropriate (brochure, website, stand, poster, etc.), as well as use any general and public information regarding services supplied by OAD to said Client.


Parties are not responsible for failure to carry out any contractual obligation if said performance failure is due to force majeure beyond their control where it could not be reasonably expected for parties to take it into consideration at the time the Contract concluded or for them to anticipate it or overcome it, even if said triggering event did not make it totally impossible to carry out contractual obligations, rather substantially more difficult or costly to do so. Force majeure events mainly include fire, strikes, accident, illness, natural catastrophes, destruction of installations or equipment, computer viruses, disruptions caused by changes in computer environment, a general lack of supplies or means of transportation and delays or performance failures by OAD suppliers or sub-contractors.

The party experiencing the difficulty in such circumstances shall give the other party prompt written notice. The obligations of parties experiencing performance failure as a result of force majeure may be provisionally suspended or renegotiated. Should the event of force majeure last more than 6 months, the Contract will be automatically terminated without payment of any damages, unless parties agree on appropriate action to fulfil the obligations of the Contract.


OAD can terminate the Contract, abandon its own obligations and retrieve the delivered CD Rom at any time without notice or compensation for the Client, ipso jure and forthwith:
- should the Client fail to carry out his/her contractual obligations or if there is serious risk that an obligation will not be performed even before this obligation is required to be carried out. In this case, all payment/s made or owed by the Client will be acquired by OAD for good, without prejudice to possible damages should the total of damages suffered by OAD turn out to be more significant in reality.
- in cases of incapacity, bankruptcy, insolvency, seizure, cessation of payment, petition for suspension of payment, amicable composition or composition approved by court, or any other event pointing to financial difficulties being faced by the Client.
- in cases of cessation of OAD’s professional activities or substantial changes thereto.
- in the case of an event of force majeure lasting over 6 months.

Should the Client terminate the Contract for any reason other than gross negligence or intentional fault by OAD, the latter will have the right in law to a lump sum as compensation equivalent to 50% of the price of the Product order placed with OAD, without prejudice to possible damages should the total cost of damages suffered by OAD turn out to be greater than this in reality.


The nullity or illegality of a provision does not affect the validity of other provisions in the Contract nor of the current general terms and conditions. Should a clause become null and void, parties agree to renegotiate a new clause in good faith which has the same objective as the original or the closest possible effect as the nullified provision, whilst respecting the law and restoring contractual equilibrium.


The Contract and current general terms and conditions are exclusively governed by Belgian Law.

Any dispute arising from an order and/or current general sales terms and conditions must be referred to the courts and tribunals of Namur.





Rue de l'Yser, 31
5020 Namur - Belgium

Phone: +32 (0)497.90.96.96


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