Exclusions specify the conditions under which the underwriter will not pay off. Moreover, the violation need not have a causal relationship with the accident. Fortunately, most policies issued by reputable companies do not carry this exclusion, but never assume this to be true. In a case of gross negligence or flagrant disregard for regulations, of course, any underwriter may question your claim. Some policies will specify pilot qualifications, an important exclusion if anyone else will be flying your airplane or if you plan to rent it or enter a leaseback agreement.
Some policies exclude flights outside the continental United States.
Some policies exclude flights made under a special waiver of the airplane's airworthiness certificate or a ferry permit. Some exclude use of the aircraft for instruction. Besides, exclusions are not the only items of concern in the fine print. Look also for implied exclusions in sections containing endorsements, definitions, conditions or limits of the company's liability. Even if damage to the engine is covered by your policy, you will only recoup the full value of a new engine if your engine was new.