I submitted a Rocket Calculator update (version 1.3) yesterday, which should be available within the next few days to a week. The changes include the following:
- Input option for elevation and temperature to compute correct air density. Used in altitude prediction as well as parachute and streamer descent rate calculators.
- Changed altitude prediction calculator input field ‘Motor case mass’ to use ‘Total motor mass’ instead. This was more intuitive, allowing the user to enter initial motor weight and propellant weight.
- Changed default descent rate for streamer calculator from 3 m/s to 4.5 m/s.
- Added missing Cesaroni motors.
- Changed app icon.
- Changed app-launch image.
- Minor bug fixes.
I just posted several videos demonstrating how to use most of the available calculators.
Version 1.2 just got approved and is available for download.
– Corrections to motor data.
– Added the motor and body tube lookup buttons to the main Altitude Prediction screen.
Coming Soon ** Temperature and elevation inputs to calculate air density. This will replace the static air density value currently used for altitude prediction and descent rate calculators.
The new update has some bug fixes and usability improvements. I also added the option to run Altitude Prediction calculations with zero drag.
I’m working on another update to the Altitude Prediction calculator that will use altitude and temperature to compute air density. Currently a static air density value is used. I’m also adding motor and body tube lookups to the main Altitude Prediction screen so they can be run without having to access the data assistant screen first.
Version 1.1.42 is available. This fixes a minor bug which affected the email response for devices that didn’t have a mail account setup. I also added a ‘Rate this App’ link to the about screen.
The App Store approved my latest update yesterday. This adds a motor look-up option to the Altitude Prediction->Data Assistant screen. It also fixes a minor issue on the Static Pressure Port calculator screen.
Here’s a screen shot from the motor look-up screen.
I added a body tube look-up feature to the Altitude Prediction calculator. There is a new button on the Data Assistant screen which will provide a list of tubes to pick from. After selecting a body tube, the tube’s diameter and area will be populated back to the Data Assistant screen. I’m currently working on motor selection option, which should be finished soon.
This update adds a few new features to the altitude prediction calculator. It will display the motor class percentage and thrust to weight ratio once a calculation is made. If the thrust to weight ratio is more than five the display is green. If less than five it is red. It will warn if the thrust ratio is less than five.
Since this calculator assumes a static drag coefficient, it will warn the user if the flight is transonic. Once a flight becomes transonic, the drag coefficient increases rapidly. For transonic flights, a static Cd could result in less accurate results.
The two warnings can be enabled or disabled by the user from the app settings.