POE DAMERON'S X-WING FLIGHT BOOSTER
The flight booster used by Poe Dameron during The Last Jedi is an improvised device made from available components compiled by technicians in the Resistance. Dameron used it in a daring and costly plan to counter attack the First Order's assault on the Resistance base at D'Qar. Poe used this booster to close distance very quickly, much faster than his T-70 X-Wing would normally be able to do, with the Fulmanitrix, a First Order Mandator IV-class star dreadnought, before the First Order's present leadership could figure out his plan. This also means Dameron was able to get under Fulminatrix's shield coverage before the dreadnought could raise its shields and prevent Dameron's attack. Having closed the distance, Dameron then proceeded to destroy all of Fulminatrix's dorsal laser cannons to open the path for a bombing run which, though costly, succeeded in destroying the star dreadnought.
Though the flight booster was impressive, it was not without its "flaws...
Model: Improvised T-70 X-wing Flight Booster
Type: Starfighter flight booster
Skill: Starfighter piloting, starfighter repair
Crew: 2 (pilot and astromech)
Ammo: 1 charge
Cost: 5,000 credits in components
Availability: 2, X*
Difficulty: See below
When used, the Flight Booster increases the speed of the starfighter it is attached to by x2. In the case of a T-70 X-Wing, this space speed boost is 16. The booster can only be used once, then it burned out and must be removed from the starfighter with tools and repair skill rolls.
The pilot must make a Difficult Stamina roll to remain conscious. Astromech droids feel the stresses of the increased speed, but due to their artificial nature they do not need to make this Stamina roll. The speed boost technically has no time limit, but does place stresses on the starfighter it is attached to that can do damage or destroy it. The first round is free, but every round after this the starfighter must make a Hull dice roll (no shield dice) against Easy Difficulty, but this increases by a Difficulty level each round after (Example: round 1, no roll; round 2, Easy; round 3, Moderate; round 4, Difficult; etc).
After the booster is activated, and after the first first round of use, the Wild Die's chance for mishaps increases. Every round from round 2 of booster use and after, the "1" on the Wold Die is increased by +1, to a max of +4 (up to 5 on the Wild Die). When such a roll is made on the Wild Die, roll a second die. If evens, there are no other issues beyond the normal Wild Die penalty (remove the Wild Die and the highest dice roll). If odds, then the penalty happens along with a mishap/malfunction. Roll on the Lightly Damaged section on the Starship Damage Chart. If the booster is used more than 5 rounds, then the section rolled on the Starship Damage Chart increases +1 section per round (6 rounds, Heavily Damaged; 7 rounds, Severely Damaged). If the booster is used for 7 rounds, the starfighter explodes and is destroyed.
[EXAMPLE: Poe Dameron and BB-8 used this booster for about 3 to 4 rounds in The Last Jedi, and immediately shut it down once they closed the gap to the Fulminatrix. Afterwards, Poe's T-70 X-Wing began experiencing malfunctions with its weapons system(s), in the form of his laser cannons being inoperative due to a power surge (which is a #3 result in the Lightly Damaged section of the Starship Damage Chart). BB-8 attempted to perform repairs, but each repair spawned another malfunction immediately afterwards, causing BB-8 to use his own body to temporarily bypass the affected systems, effectively jury rigging to get the laser cannons back online.]
If players wish to make their own Flight Booster of this type, they just need to gather 5,000 credits worth of components that are easily available anywhere where repair parts and tools can be purchased or bartered for for starfighters or similar sized starships. A Very Difficult Starfighter Repair skill roll must be made, and it takes 6-12 hours to make (3-6hrs of they can make Heroic), then another Moderate Starfighter Repair roll and 2-4 hours to attach to the starfighter (1-2hrs if they make Difficult, 30min-1hr for Very Difficult). This flight booster must be CUSTOM MADE for each starfighter it is made for. If there were a commercial version, it would not be so prone to malfunctions, and this booster here is built using straight-up jury rigging of available components.
Once built, if worked on after completion, but before use and activation, with the Starfighter Engineering skill, these malfunctions can be reduced in severity, and eventually be worked out all together and create a stable flight booster. If worked on in this way, the booster can also become reusable and not a one-time-use device. If making these repairs, refer to the charts found in Galaxy Guide 6 Tramp Freighters and/or Star Wars Rulebook Revised and Expanded. If these charts list limits to how far they can be used, ignore these and keep going as the booster is an improv creation being worked on and improved less as a standard, and more as a hobby and art.
Availability is listed as 2 X, available only in large cities or spaceports (or properly stocked Resistance or Rebellion bases), and illegal on most planets. The illegal part, even if this were being used during the Old Republic during peace time, this flight booster would be seen as highly dangerous and use of such a thing would be considered reckless and immature, to say the least, let alone what the Galactic Empire or First Order would do to someone who used one against them.
[NOTE!: This write-up is not made based on official information. At the time of this write-up there is little-to-no information available to use, and much of this was made up using info scraps, guesswork, imagination and creativity. Future official info releases may render this write-up incompatible with the Star Wars canon.]