While phantom body tubes have a number of uses in OpenRocket, the use of a phantom body tube to enclose motor mounts (centering rings and the motor tube) prevents some of the OpenRocket features from functioning corrently. And, there is simply no reason to use a phantom body tube in this manner.
Moreover, those who use phantom body tubes should be aware of the warnings that may be triggered. The best example of which is the use of a phantom body tube to attach a fin shaped like an Estes motor hook. When this hack is used, a series of warnings is triggered: (1) discontinuity because the phantom tube (an airframe component) is a different diameter than that of the adjacent airframe component; (2) thick fins because because of the ratio between the phantom tube diameter and the width of the fin (motor hook); and (3) jagged-edged fin because of the shape of the motor hook. This use of the phantom tube is currently necessary to achieve the desired effect and does not interfere with other OpenRocket functions, though Issue #1522 proposes a new feature so that the use of a phantom tube for this purpose will no longer be required.
A phantom body tube is an aerodynamic component that may affect flight characteristics, in addition to preventing some of the OpenRocket features from functioning corrently. To the extent that a design can be created without the use of phantom body tubes, normal design techniques should be used; the use of phantom body tubes should serve a purpose that cannot otherwise be achieved.
Moreover, those who use phantom body tubes should be aware of the warnings that may be triggered. The best example of which is the use of a phantom body tube to attach a fin shaped like an Estes motor hook. When this hack is used, a series of warnings is triggered: (1) discontinuity because the phantom tube (an airframe component) is a different diameter than that of the adjacent airframe component; (2) thick fins because because of the ratio between the phantom tube diameter and the width of the fin (motor hook); and (3) jagged-edged fin because of the shape of the motor hook. This use of the phantom tube is currently necessary to achieve the desired effect and does not interfere with other OpenRocket functions, though Issue #1522 proposes a new feature so that the use of a phantom tube for this purpose will no longer be required.
A phantom body tube is an aerodynamic component that may affect flight characteristics, in addition to preventing some of the OpenRocket features from functioning corrently. To the extent that a design can be created without the use of phantom body tubes, normal design techniques should be used; the use of phantom body tubes should serve a purpose that cannot otherwise be achieved.
