Slow-motion footage revealed the spiders used their silk draglines to stabilise their bodies and to brake, enabling them to land poised and ready to pounce on prey.
The discovery, the scientists say, could inspire new robot design.
It is published in the Royal Society journal Interface.
Kai-jung Chi, from National Chung Hsing University in Taiwan, and her colleagues investigated the jumping ability of Adanson's house spider, a common arachnid that jumps when it hunts, in order to surprise its prey.
Ultimately, Dr Chi and her team hope to learn exactly how these creatures fine-tune and control their jumping manoeuvres, to aid the design of miniature robots able to move in similar ways.
Dr Chi's colleague, PhD student Yung-Kang Chen, filmed the spiders at 1,000 frames per second, and slowed down the resulting footage. They compared the movements of the Adanson's spider with those of a species of jumping spider that does not use a silk dragline.
"We analysed the motion and body orientation throughout the jumps," Dr Chi told BBC News.
This revealed that the Adanson's spider used its dragline to control the orientation of its body mid-air and to brake as it landed.
The non-silk jumping spider would often lose balance - tipping forward and onto its back upon landing.
"[The silk means that the spiders] can land in the optimal position to rapidly initiate prey capture," Dr Chi said.
The results, she said, suggested that the spiders were taking up the slack in their silk dragline by using the valve in their spinning system.
These super-fast adjustments mean that silk provides more than just a safety line for a jumping spider.
Dr Chi said that the "adjustable silk tension" could provide "biological inspiration" for future manoeuvrable robot design.

Watkins has been banned for four years after he tested positive for the anabolic steroid nandrolone and the stimulant methylhexaneamine.
He joins team-mate Shaun Cleary, who has been banned for two years as benzoylecgonine, a cocaine metabolite, was found in his system.
Both players tested positive before a friendly against Bridgend Ravens RFC.
UKAD Director of Legal, Graham Arthur said: "Ryan Watkins deliberately ingested nandrolone and methylhexaneamine without any consideration for his responsibilities as an athlete.
"By making this conscious choice to dope, Watkins has chosen to cheat his team-mates, the opposition and his sport.
"I hope this case will act as strong deterrent to other young amateur players - the risks to your playing career, your reputation and more importantly to your health, just aren't worth it."
Speaking about Cleary, Mr Arthur said:  "Although Mr Cleary used cocaine three days before playing, cocaine was still in his system when he played.
"Cocaine is banned from sport and athletes are solely responsible for what is in their system, regardless of whether there is an intention to cheat or not."
Welsh Rugby Union chief executive Martyn Phillips said about Cleary: "This case serves as a strong warning to everyone in the game that non-compliance with anti-doping rules carries grave consequences.
"Whether intentional, or inadvertent, players have a responsibility to themselves, to each other, to their clubs and to the sport to act within the rules and spirit of the game.
"We work closely with UK Anti-Doping and fully adhere to the World Anti-Doping Code. There is no room in the code for carelessness or not knowing.
"We will be relentless in working with UKAD to follow up leads that out players who dope in Welsh rugby."
Maesteg Harlequins are mid-table in Welsh National League Division One West Central and Cleary has been banned until 10 October, 2017. Watkins is banned until 11 September 2019.
High-speed cameras have revealed how jumping spiders use a dragline of silk to stabilise themselves mid-air and control their landings.
[NEXT_CONCEPT]
Maesteg Harlequins lock Ryan Watkins has become the 12th Welsh rugby player to be suspended by UK Anti-Doping.