| 摘要 |
<p>THE This invention is directed to a marker which can be dropped from an airplane so that the pilot of an airplane can see the marker on the ground and know, when he is in the airplane, where the airplane has flown for spraying fertilizer, insecticides, herbicides, and the like. The drop marker comprises a base member of flexible corrugated board and a reinforcing plate attached to the base member. There is also a streamer material which is attached to the base member and which unfolds when the drop marker falls from the airplane toward the ground. The drop marker, upon reaching the ground and with the streamer unfolded, makes it possible for the pilot of the airplane to know where he has sprayed the chemical carried by the airplane.</p> |
