Parachute Hatch

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Parachute Hatch Icon.png
Large Ship Icon.png
Large Ship / Station
Parachute Hatch
 
Components
Required

 

 
 
3
 
 
Mass (kg):
472.4
 
Integrity:
1847
 
Build time (seconds):
24
 
Disassemble Ratio:
1.5
 
Active power consumption (MW):
0.001
 
Idle Power Consumption (MW):
0.00001
 
Airtight:
Yes - all orientations
 
Power Consumer Group:
Doors
 
Dimensions (W x H x D):
1 x 1 x 1
Parachute Hatch Icon.png
Small Ship Icon.png
Small Ship
Parachute Hatch
 
Components
Required

 

 
 
1
 
 
Mass (kg):
84.2
 
Integrity:
316
 
Build time (seconds):
24
 
Disassemble Ratio:
1.5
 
Active power consumption (MW):
0.001
 
Idle Power Consumption (MW):
0.00001
 
Airtight:
Yes - all orientations
 
Power Consumer Group:
Doors
 
Dimensions (W x H x D):
1 x 1 x 1

Overview

The Parachute Hatch is a re-loadable parachute deployment block. It consumes Canvas materials with each deployment (1 for small grid, 5 for large grid), but is otherwise reusable. It allows players to rapidly slow their craft in-atmosphere (regardless of which direction they are moving in) and/or gently lower their craft to the ground. Thus, players can deliver craft or items from orbit to ground without requiring expensive thrusters on the craft to prevent a crash. It can also be used as a backup landing mechanism in case too many lift thrusters are damaged or destroyed. The block itself is based on the Ship Parachutes mod which was developed by Harax, Mexpex and Draygo.

Usage

To use, place 1 or more parachute hatches on your craft and stock them with canvas. It is recommended to keep parachutes aligned with your center-of-mass, since once the parachute is opened your craft will hang from it at whatever point it is attached. The parachute can be deployed manually by "Opening" the hatch, or automatically at a specified altitude. The hatch will "Close" and the parachute will be automatically detached (and cease to exist) when the craft comes to a complete stop either on the ground or in a hover (if the craft has sufficient downwards thrust and dampeners enabled). The hatch can also be manually closed at any time, discarding the parachute.

Control Panel

Open / Closed Deploys ("Open") or detaches ("Closed") the parachute.
Auto deploy Whether auto deploy is on or off
Auto deploy height Height that the parachute will automatically deploy if auto deploy is On
Min: 10m  Max: 10,000m

Terminal Velocity

When deployed, parachutes quickly slow the craft to a fraction of its original speed, however they do not immediately slow the craft to its terminal velocity. After the rapid deceleration immediately following deployment, the craft will gradually slow to its terminal velocity.

It is possible to calculate a craft's terminal velocity, in order to gauge how soft or hard the landing will be:

Ship-specific variables

MASS - in kg
GRIDSIZE - 0.5 for small grid parachute, 2.5 for large grid parachute
QTY - number of parachutes

Planet-specific variables

GRAVITY - in m/s2 (9.81 for Earth-like planets)
ATM - atmosphere, changes with altitude (from 0 to 1.0 on Earth-like planets)

Constants

RADMULT - radius multiplier, always = 8
REEFLEVEL - reefing level, always = 0.6
CD - drag coefficient, always = 1.0

Calculations

parachute diameter = (log((10*(ATM-REEFLEVEL))-0.99)+5)*RADMULT*GRIDSIZE

area = PI*(diameter/2)^2

terminal velocity = squareroot((MASS*GRAVITY)/(area*CD*QTY*ATM*1.225*2.5))

Example: Standard Red Ship

MASS = 2927310
GRIDSIZE = 2.5 (large grid)
QTY = 10 (it's a big ship!)
GRAVITY = 9.81 (we'll say this is an Earth-like planet)
ATM = 0.85 (avoid using 1.0 - 0.85 gives a more conservative result)

diameter = (log((10*(ATM-REEFLEVEL))-0.99)+5)*RADMULT*GRIDSIZE
         = (log((10*(0.85-0.6))-0.99)+5)*8*2.5
         = 103.6

area = PI*(diameter/2)^2
     = 8,429.6

terminal velocity = squareroot((MASS*GRAVITY)/(area*CD*QTY*ATM*1.225*2.5))
                  = squareroot((2927310*9.81)/(8429.6*1.0*10*0.85*1.225*2.5))
                  = 11.4 m/s

Media

Tips

  • Parachutes and mountains do not get along. Where possible, try to use a parachute over low-elevation terrain.
  • Large grid parachutes have 25x more drag than a small grid parachute. Use large grid parachutes for heavy drops.
  • Parachute drag will oppose your direction of motion in atmosphere, even if you are trying to fly UP.
  • You need electrical power on a grid to deploy or cut the chutes, but while the chutes are deployed power is not strictly necessary. The parachute will stay out while the power is gone, and will even stay out if the block is damaged to a non-functional state!
  • On a ship with low weight and many parachutes, parachutes might automatically cut when the ship velocity drops below 2 m/s. If you start falling because of this then the chutes will re-deploy if set for automatic deployment. In Survival Mode this would cause you to expend more canvas. If this happened repeatedly, you could run out of canvas before reaching the ground.

Known Issues

Programming

Update History

Update 1.183.1
  • Fixed parachute not working with conveyor system
Update 1.183.0
  • Parachute Hatch introduced