I'm building a model rocket that will probably go a maximum of 30km. Do I need special permission from the FAA to do this? I'm in Delaware, U.S.A., and this is a Class 1 Model Rocket. If I do, where can I get started? And do I need a licence or just permission?
The FAA regulates amateur model rocketry under 14 CFR 101, Subpart C.
For a Class 1 model rocket:
(a) Class 1 - Model Rocket means an amateur rocket that:
(1) Uses no more than 125 grams (4.4 ounces) of propellant;
(2) Uses a slow-burning propellant;
(3) Is made of paper, wood, or breakable plastic;
(4) Contains no substantial metal parts; and
(5) Weighs no more than 1,500 grams (53 ounces), including the propellant.
The following are the general limitations:
(a) You must operate an amateur rocket in such a manner that it:
(1) Is launched on a suborbital trajectory;
(2) When launched, must not cross into the territory of a foreign country unless an agreement is in place between the United States and the country of concern;
(3) Is unmanned; and
(4) Does not create a hazard to persons, property, or other aircraft.
(b) The FAA may specify additional operating limitations necessary to ensure that air traffic is not adversely affected, and public safety is not jeopardized.
And specific requirements for notification are outlined as:
No person may operate an unmanned rocket other than a Class 1 - Model Rocket unless that person gives the following information to the FAA ATC facility nearest to the place of intended operation no less than 24 hours before and no more than three days before beginning the operation:
(a) The name and address of the operator; except when there are multiple participants at a single event, the name and address of the person so designated as the event launch coordinator, whose duties include coordination of the required launch data estimates and coordinating the launch event;
(b) Date and time the activity will begin;
(c) Radius of the affected area on the ground in nautical miles;
(d) Location of the center of the affected area in latitude and longitude coordinates;
(e) Highest affected altitude;
(f) Duration of the activity;
(g) Any other pertinent information requested by the ATC facility.
There are no regulations for launches/operator to obtain a specific license if the model rocket motor complies with those in the quoted text.
While this regulation says you don't have to notify anybody, since you are expecting a significant altitude flight (and speaking as a pilot), it would be nice if you did notify them, especially if you are within a few miles of an airport or airway.