One of the first thing I wanted to add to Freeciv after playing game or two. My suggestions:
1. Cheap, early accessible air units. May be upgrade from Baloons. The Baloons might have 3/4 chance of random movement when not on Sentry or in city, no defence and dying if stuck over the sea. Zeppellins may also be affected by wind for getting +1mp or -1mp randomly. Don't know can it be realized with existing movement mechanics.
2. Can transport any land unit, even heavy.
3. Probably non-military. Or with very low attack.
4. Main disadvantages - relatively slow (like 2mp) and extremely brittle (like 1def/1hp). Implementing brittleness requires a way for land units to attack them. Can declare them "Both" type unit, like Helicopters, or give some bombardment mechanics to most units to shoot insccessible enemies.
5. Additionally, requires mast to operate - crashes if unloaded outside of city or base (but when doing so over land and intentionally, the transported unit survives). So desanting artillery on another continent inlands is possible but dangerous, expensive and one-way.
6. As a mad idea, defensive aerostats! Block Bombers and prevent attack of Fighters on more expensive targets. May imbalance the game against aviation though.
Added:
7. Maybe deprecated by Helicopters. Of course (considering civ2civ3) Helicopters have disadvantages as shortened range and limited weight, but in real life they effectively pushed dirigibles out of use for obvious advantages. It's like Transport deprecates Trireme while it can't enter rivers - for gameplay, it makes powerful advances less overpowered.
And thanks to our Transnistrian friends, such a unit is found included in
po-russki ruleset (
topic)

! Here is its units.ruleset listing with some my (;; ...) comments and picture:
Code: Select all
[unit_dirijabl]
name = _("Дирижабль");;dirigible
class = "Helicopter"
tech_req = "Theory of Gravity";; /* Maybe not so early, Baloon should be then,
;; and it would come with "Flight" - just look at the tech's standard icon! */
obsolete_by = "Helicopter"
graphic = "dirijabl"
graphic_alt = "-"
sound_move = "m_dirijabl"
sound_move_alt = "m_generic"
sound_fight = "f_howitzer"
sound_fight_alt = "f_generic"
build_cost = 100 ; цена ;; price, I would like it costed 60 as Fighter or even less
pop_cost = 0
attack = 6 ;; yes, IRL it had attack, see first post
defense = 3 ;; too much IMHO
hitpoints = 20 ;; also... but you haven't seen other units in this RUleset!
firepower = 2
move_rate = 8 ; шаги ;;steps
vision_radius_sq = 8
transport_cap = 4 ;; I think 1 is enough
fuel = 0
uk_happy = 1
uk_shield = 0
uk_food = 0
uk_gold = 0
cargo = "Land" ; может перевозить грузы ;; may carry load. /* In civ2civ3 should be "Land", "Small Land", "Big Land", "Merchant"
;; but with some tweaks to avoid loading all unit types out of a base
flags = "FieldUnit", "Helicopter", "BadCityDefender" ;; in civ2civ3, if we give it attack, also should be "Bombarder"
roles = ""
helptext = _("\
Дирижабль переносит грузы (до 4 единиц) в любых условиях и на любые расстояния.\
");;Dirigible carries loads (up to 4 items) at any conditions on any distance.

- dirijabl.png (2.36 KiB) Viewed 18031 times
no copyright info found but probably (c) Anatoly Bessarab, 2015