<p>We have been thinking of using Aerostats/Balloons for an environmental monitoring project in our university. We have been considering 2 options: Tethered Aerostats (which fly upto 1 km) and Stratospheric Aerostats (upto 20 - 30 km).</p>

<p>As I was exploring the available options, I was surprised to find that Tethered Aerostats (i.e. low-altitude balloons, within 1km) have much less persistence in air than Stratospheric Balloons. E.g. Airstar's <a href="http://airstar.aero/en/tethered-balloons-range/" rel="nofollow noreferrer">tethered balloons have maximum persistence of 15 days</a> while their <a href="http://airstar.aero/en/stratospheric-balloons/" rel="nofollow noreferrer">stratospheric versions can hover for upto 6 months</a>.</p>

<p>What is the reason? Is it the wind speed? Or less density (but how would it affect)? Or maybe it's just they are designing the stratospheric balloons to last longer?</p>

CC BY-SA 4.0
2018-11-02T23:53:10.977Z
A good question... not sure anybody here is nearly an expert enough on such topics to have good input... but may get some more theorizing...
JeopardyTempest
CC BY-SA 4.0
2018-11-02T23:53:35.810Z
The site seems to have some imperfect translations of words at times.
JeopardyTempest
CC BY-SA 4.0
2018-11-02T23:57:33.147Z
I noticed the critical wind speed of the strongest troposphere balloon is only 150 km/hr (93 mph).  But below 1 km such wind speeds shouldn't be very common.  So I don't think it's that at those low elevations?
JeopardyTempest
CC BY-SA 4.0
2018-11-03T00:00:31.050Z
The pressures are a ton higher in the stratosphere, so maybe it is about durability?  There's also stability in the stratosphere, plus fairly modest wind speeds in most spots [it appears](https://www.britannica.com/science/climate-meteorology/Winds-in-the-stratosphere-and-mesosphere).  Maybe the strains of the pull tethering it in place has consequences!?!
JeopardyTempest
CC BY-SA 4.0
2018-11-03T00:02:34.100Z
In the end, wonder if maybe it'll be better to have a moderator move the question to the aviation forum, as they may be more familiar with the balloon aspects (and perhaps more keyed in atmosphere conditions aloft too).  But perhaps wait and see if anyone has input here, and then a moderator can move it.  Good/interest question, definitely, and welcome to our part of the SE world :)
JeopardyTempest
CC BY-SA 4.0
2018-11-03T00:09:15.927Z
You should see this related post: https://earthscience.stackexchange.com/questions/8/why-are-weather-kites-no-longer-used-much-operationally/1070#1070  I think the answer to your question is because a tethered system does not float freely and can be deteriorated or broken due to winds and storms.
f.thorpe
CC BY-SA 4.0
2018-11-03T03:44:33.767Z
@JeopardyTempest Thank you for the warm welcome. Yes. I think moving the question to aviation forum might be better. But let's a little while and see what responses we get from here.
shivams
<meteorology><atmosphere><weather-satellites>
Why do tethered aerostats have lower persistence than stratospheric balloons?
shivams
# Why do tethered aerostats have lower persistence than stratospheric balloons?

(Asked by: username_0 on 2018-11-02)

We have been thinking of using Aerostats/Balloons for an environmental monitoring project in our university. We have been considering 2 options: Tethered Aerostats (which fly upto 1 km) and Stratospheric Aerostats (upto 20 - 30 km).

As I was exploring the available options, I was surprised to find that Tethered Aerostats (i.e. low-altitude balloons, within 1km) have much less persistence in air than Stratospheric Balloons. E.g. Airstar's [tethered balloons have maximum persistence of 15 days](http://airstar.aero/en/tethered-balloons-range/) while their [stratospheric versions can hover for upto 6 months](http://airstar.aero/en/stratospheric-balloons/).

What is the reason? Is it the wind speed? Or less density (but how would it affect)? Or maybe it's just they are designing the stratospheric balloons to last longer?

**Tags:** meteorology, atmosphere, weather-satellites

> **Comments:**
> **username_1**: A good question... not sure anybody here is nearly an expert enough on such topics to have good input... but may get some more theorizing...  
> **username_1**: The site seems to have some imperfect translations of words at times.  
> **username_1**: I noticed the critical wind speed of the strongest troposphere balloon is only 150 km/hr (93 mph).  But below 1 km such wind speeds shouldn't be very common.  So I don't think it's that at those low elevations?  
> **username_1**: The pressures are a ton higher in the stratosphere, so maybe it is about durability?  There's also stability in the stratosphere, plus fairly modest wind speeds in most spots [it appears](https://www.britannica.com/science/climate-meteorology/Winds-in-the-stratosphere-and-mesosphere).  Maybe the strains of the pull tethering it in place has consequences!?!  
> **username_1**: In the end, wonder if maybe it'll be better to have a moderator move the question to the aviation forum, as they may be more familiar with the balloon aspects (and perhaps more keyed in atmosphere conditions aloft too).  But perhaps wait and see if anyone has input here, and then a moderator can move it.  Good/interest question, definitely, and welcome to our part of the SE world :)  
> **username_2**: You should see this related post: https://earthscience.stackexchange.com/questions/8/why-are-weather-kites-no-longer-used-much-operationally/1070#1070  I think the answer to your question is because a tethered system does not float freely and can be deteriorated or broken due to winds and storms.  
> **username_0**: @username_1 Thank you for the warm welcome. Yes. I think moving the question to aviation forum might be better. But let's a little while and see what responses we get from here.  

---

## 0 answers

