diff --git a/docs/documentation/sizing/create_mission_xml/index.md b/docs/documentation/sizing/create_mission_xml/index.md index 6993510642099373531e21df71538d7f5deb2d64..33892231d6d72779104ea28d16b2123c3deb5c08 100644 --- a/docs/documentation/sizing/create_mission_xml/index.md +++ b/docs/documentation/sizing/create_mission_xml/index.md @@ -3,9 +3,9 @@ Good news first: **create_mission_xml** is quite slim... or perhaps the slimmest tool of the whole UNICADO chain. It's sole purpose is to define some basic parameters and target points on the mission's trajectory. Nonetheless, this is critical to the whole operation, because we all know *if you fail planning, you'll be planning your failure!* But no worries, we'll help you out :wink: -## What a mission looks like +## What a Mission Looks Like {#typical_mission} -In short, a mission contains a handful of so-called segments with which you can define a basic mission profile. Depending on the aircraft size, regulation and flight path planning philosophy, some details may differ, but in general is should look something like this: +In short, a mission contains a handful of so-called segments with which you can define a basic mission profile. Depending on the aircraft size, regulation and flight path planning philosophy, some details may differ, but in general it should look something like this: <p align="center"> <img src="figures/flight_path.png" alt="Flight segments" width="97.5%"> diff --git a/docs/documentation/sizing/create_mission_xml/mission_steps.md b/docs/documentation/sizing/create_mission_xml/mission_steps.md index 8f440623a1805a3a0ab8fa7ac51abc93124c9f3e..1a8d22e63fe9bbf1f7bdcd9a904c4e49962657fe 100644 --- a/docs/documentation/sizing/create_mission_xml/mission_steps.md +++ b/docs/documentation/sizing/create_mission_xml/mission_steps.md @@ -24,10 +24,10 @@ The steps in the `mission_file` can be filled and arranged in different ways, de | accelerate | climb thrust setting | clean | N/A | 6.10 (1200 fpm) | CAS ATC limit climb | | climb | climb thrust setting | clean | 3048 (10,000 ft) | maximum rate of climb | N/A | -In the standard procedure, we assume that the thrust-to-weight ratio is high enough to maintain minimum safe climb speed $v_2$ (see pic) from takeoff until en-route transition at $3\,000\,ft$. Therefore, the aircraft shall climb with the given `maximum_rate_of_climb` and `climb_thrust_setting` from the [Configuration File](getting_started.md/#config_file) without an acceleration in between. Since the landing gear gets retracted between screen height ($35\,ft$) and $1\,500\,ft$, climbing up to $3\,000\,ft$ is divided into two segments. Like this, it's easier [Systems Design](../systems_design/index.md) to simulate the retraction and to put the power/bleed air demand into the `mission file`. Once en-route transition is reached, flaps are set to `climb` while accelerating to $210\,kt$ calibrated airspeed. Just after that, the aircraft accelerates further in `clean` configuration (least drag) until the _CAS_ATC_limit_climb_ is obtained. Since the air space below $10,000\,ft$ is more crowded, institutions like FAA and ICAO limit the speed to $250 kt$ calibrated airspeed, but you can change that in the `climb_speed_below_FL100` node of our [Aircraft Exchange File](getting_started.md/#acxml). Then, the aircraft finishes the departure procedure by climbing up to $10,000\,ft$ using the `maximum_rate_of_climb`. +In the standard procedure, we assume that the thrust-to-weight ratio is high enough to maintain minimum safe climb speed $v_2$ (see [What a Mission Looks Like](index.md/#typical_mission)) from takeoff until en-route transition (`climb` configuration) at $3\,000\,ft$. Please mind, that EASA's CS-25 only allows extrapolation of the propulsion system's takeoff performance data up to that altitude. To do so, the aircraft shall climb with the given `maximum_rate_of_climb` and `climb_thrust_setting` from the [Configuration File](getting_started.md/#config_file) without an acceleration in between. Since the landing gear gets retracted between screen height ($35\,ft$) and $1\,500\,ft$, climbing up to $3\,000\,ft$ is divided into two segments. Like this, it's easier [Systems Design](../systems_design/index.md) to simulate the retraction and to put the power/bleed air demand into the `mission file`. Once en-route transition is reached, flaps are set to `climb` while accelerating to $210\,kt$ calibrated airspeed. Just after that, the aircraft accelerates further in `clean` configuration (least drag) until the _CAS_ATC_limit_climb_ is obtained. Since the air space below $10,000\,ft$ is more crowded, institutions like FAA and ICAO limit the speed to $250 kt$ calibrated airspeed, but you can change that in the `climb_speed_below_FL100` node of our [Aircraft Exchange File](getting_started.md/#acxml). Then, the aircraft finishes the departure procedure by climbing up to $10,000\,ft$ using the `maximum_rate_of_climb`. !!!node - Although `maximum_rate_of_climb` can be set as a constant value, we usually set it to $-1$ to indicate that the aircraft shall use all possible thrust of its current engine settings to achieve altitude gains. Therefore, rate of climb varies within these `climb` segments. Since acceleration is most effective and saver when keeping a constant rate of climb, it is manually set to $1\,000\,\frac{ft}{min}$/$1\,200\,\frac{ft}{min}$ which follows the ICAO's recommendations. + Although `maximum_rate_of_climb` can be set as a constant value, we usually set it to $-1$ to indicate that the aircraft shall use all possible thrust of its current engine settings to achieve altitude gains. Therefore, rate of climb varies within these climb segments. Since acceleration is most effective and saver when keeping a constant rate of climb, it is manually set to $1\,000\,\frac{ft}{min}$/$1\,200\,\frac{ft}{min}$ which follows the ICAO's recommendations. ### Standard 19 seat commuter @@ -115,7 +115,7 @@ The first approach segment starts at $10\,000\,ft$ where the descend speed limit | descend | cruise | landing | 15.24 (50 ft) | -3 | N/A | | landing | takeoff | landing | 0 | -3 | N/A | -For smaller aircraft, the approach procedure becomes less complicated. You can simply decelerate to the before mentioned CAS limit of $250\,kt$ before descending towards initial approach fix at $2\,000\,ft$. Next the aircraft's configuration is set to `approach` while decelerating to $v_{max, approach}$ with which we bring it to the ground using its `landing` configuration. Easy peasy lemon squeezy! :lemon: +For smaller aircraft, the approach procedure becomes less complicated. You can simply decelerate to the before mentioned CAS limit of $250\,kt$ before descending towards initial approach fix at $2\,000\,ft$. Next, the aircraft's configuration is set to `approach` while decelerating to $v_{max, approach}$ with which we bring it to the ground using its `landing` configuration. Easy peasy lemon squeezy! :lemon: ### (Steep) Continuous Descent Approach