# 6.1 Selection of Airframes
The airframe is the chassis that holds all the components, and payloads on it. Its size and capacity are very much concerned with the construction of drones. As discussed in 1st module of the Certification Course - PCDP, the selection of airframes should be proper to carry the weight of all the components of a drone. Selection of the proper airframe is necessary as it is associated with the firmware of the system.
RPA Configuration -Airframe
The Airframe setting can be done to choose the required airframe so that flight controller software can understand and operate accordingly. This is a very important setting and must be ensured before a flight is taken. It has two types of settings.
a) **Frame Class** All the standard classes of airframe supported by Ardupilot and PX4 firmware are displayed here. You need to select on of them and reboot the drone.
b) **Frame Type:** All the standard frame types of airframe supported by Ardupilot and PX4 firmware are displayed here. You need to select one of them as per drone's physical specifications.
Selection of Frame Type
After selecting the class and type of airframe click on the "Update" button to update the parameters.
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://aerogcs-docs.aeromegh.com/5-rpa-configuration/6.1-selection-of-airframes.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.