Issue 023 - Military logistics - Sorties and fuel
What does a two-hour strike wave require?
Reuters reported that U.S. forces carried out a fresh strike wave against dozens of Iranian military targets on July 29, 2026. CENTCOM said the strikes ran from 8 p.m. to 10 p.m. ET. That is the attack window, not necessarily the full flight time of every aircraft involved.
The problem
Estimate the logistics behind a two-hour strike wave against dozens of Iranian military targets.
Estimate:
- The number of strike-aircraft sorties required.
- The total aircraft-hours flown, including strike, tanker, surveillance, command, and electronic-warfare aircraft.
- The total jet fuel consumed.
- The number of aerial-tanker loads or tanker sorties needed.
Then decide whether the main logistical burden was probably the weapons dropped, the fuel burned by strike aircraft, or the supporting aircraft needed to conduct and protect the operation.
Because Fermi problems target an order of magnitude, I normally use no more than two significant digits and write most calculations in scientific notation; the Fermi reference explains both conventions.
Before checking sources
Matt's first pass
First for missiles, I assumed about 3 missiles per target and about $225,000 per missile, which gives about 72 missiles and about $18 million spent on those missiles.
Next for striker aircraft, I assumed an average jet mass of about 8 x 10^4 kg, an average mission flight time of 3 hours, an average airspeed of about 300 m/s, and that the big fuel drain would be air resistance during flight.
If I assume about 1 meter of drop per 20 meters traveled, the force of air resistance to overcome would be like paying back the potential energy for that total drop.
flight time ~= 3 hours
~= 1.1 x 10^4 seconds
distance per plane ~= 300 m/s x 1.1 x 10^4 s
~= 3.3 x 10^6 m
effective drop ~= 3.3 x 10^6 m / 20
~= 1.6 x 10^5 m
energy per plane ~= mgh
~= 8 x 10^4 kg x 10 m/s2 x 1.6 x 10^5 m
~= 1.3 x 10^11 JAssuming 50% efficiency and 4.5 x 10^7 J per liter of jet fuel, that gives about 2.3 x 10^7 J of useful work per liter. Dividing that into 1.3 x 10^11 J gives about 5.6 x 10^3 liters of jet fuel per plane.
I do not know what jet fuel costs per liter, but assuming about $3/L, that is about $17,000 per striker aircraft. If my estimate of 50 striker aircraft is correct, that is about $850,000 on fuel for the strikers.
Counting all other aircraft involved in the mission, I bet that multiplies the total fuel cost by 3x. So I estimate fuel cost for the mission was about $2.6 million.
So I am guessing we still spent 7x as much on missiles as we did on fuel costs for all mission-related aircraft.
Calibration Score
Matt's Calibration Score: 80 / 100
Higher is better: earn points for accurate pegs, sound models, correct math, and a result close to the sourced answer. The image shows percent full of it: 100 minus the Calibration Score.
Pegs: 20/30. Missile and aircraft pegs were imperfect but usable.
Model: 30/30. Separating munitions, aircraft fuel, tanker support, and package logistics was the right model.
Math: 10/10. The arithmetic was clean.
Result: 20/30. The fuel-cost and overall cost-scale conclusions were close enough for Fermi work.
Grounding facts
The U.S. Air Force lists the F-15E Strike Eagle as an air-to-ground attack aircraft with a 37,500-pound empty weight, 81,000-pound maximum takeoff weight, and 35,550-pound fuel capacity when using conformal fuel tanks and three external tanks. That makes Matt's 80,000-kg aircraft-mass guess high, but not absurd if he was mentally picturing a fueled and loaded aircraft plus roughness.
Official tanker facts show why refueling is its own logistics problem. The KC-135 exists to provide aerial refueling capability, and the KC-46A lists more than 212,000 pounds of fuel capacity. But a tanker has to fly to the refueling track, keep reserves, and often support multiple receivers across a carefully timed package.
The strike window is therefore a misleadingly small time number. Two hours of attacks can imply hundreds of total aircraft-hours once the support package is included.
After checking sources
Check and recalibrate
The public facts do not reveal the force package, so the answer should stay as a bracket. Start with the target count. "Dozens" could mean about 24 to 60 targets; use 40 targets as the central estimate.
targets ~= 40
weapons per target ~= 2
total weapons ~= 40 x 2
~= 80 weaponsIf a strike aircraft handles about two to four weapons or target points on average, the strike-aircraft count is roughly:
strike sorties ~= 80 weapons / 3 weapons per sortie
~= 30 strike sortiesA good bracket is about 20 to 50 strike sorties. Matt's 50-strike-aircraft estimate is toward the high end, but still plausible for a large, distributed strike wave if targets are spread out or if the package includes escorts counted as strike aircraft.
The bigger hidden variable is that a two-hour strike window is not a two-hour mission. Aircraft may have launched from regional bases, carriers, or more distant staging points, then refueled, joined packages, held, attacked, and returned. Use about 5 hours per strike sortie as a central placeholder:
strike aircraft-hours ~= 30 strike sorties x 5 hours
~= 150 aircraft-hoursSupport can match or exceed that. Tankers, electronic-warfare aircraft, surveillance aircraft, command-and-control aircraft, escorts, combat air patrol, and rescue coverage can easily add another one to two aircraft-hours for every strike aircraft-hour:
support aircraft-hours ~= 2 x strike aircraft-hours
~= 300 aircraft-hours
total aircraft-hours ~= 150 + 300
~= 450 aircraft-hoursSo a reasonable total is about 300 to 700 aircraft-hours, even though the visible attack wave lasted only about two hours.
Fuel is the next translation. The physics route Matt used is actually a good Fermi shortcut because lift-to-drag ratio turns horizontal flight into an equivalent "climb" that must be paid for with fuel. The aircraft mass was high, the assumed efficiency was high, and the fuel price was high, but the fuel-per-jet answer stayed in the right neighborhood.
Use a simpler operational peg: a strike fighter on a serious mission might burn roughly 5 metric tons of fuel per flight-hour, or about 6,000 liters per hour. That is intentionally rough and includes high-power phases, combat routing, and reserve/loiter margin.
strike fuel ~= 150 aircraft-hours x 5 tonnes/hour
~= 750 tonnes
liters ~= 750,000 kg / 0.8 kg/L
~= 9 x 10^5 LSupport aircraft are mixed. Some are large tankers or command aircraft; some are fighters or electronic-attack aircraft. Use an average support burn around 5 to 7 tonnes per hour:
support fuel ~= 300 aircraft-hours x 6 tonnes/hour
~= 1,800 tonnes
total fuel ~= 750 + 1,800 tonnes
~= 2,500 tonnes
~= 3 x 10^6 liters
~= 8 x 10^5 gallonsAt EIA's July 2026 Gulf Coast jet-fuel spot price of roughly $3.5/gallon, that fuel is on the order of:
fuel cost ~= 8 x 10^5 gallons x $3.5/gallon
~= $3 x 10^6So Matt's roughly $2.6 million total fuel estimate was very close as a cost-scale answer.
For tanker loads, use KC-46 scale as the clean official peg: its fuel capacity is about 212,000 pounds. Not all of that is useful offload after the tanker flies its own mission, so use about 100,000 pounds of transferable fuel per tanker sortie as a simple planning number.
fuel needing tanker delivery ~= 1 x 10^6 to 2 x 10^6 lb
tanker sorties ~= delivered fuel / 1 x 10^5 lb per tanker sortie
~= 10 to 20 tanker sortiesThat is not a claim about the actual mission count; it is a scale estimate. The tanker burden can grow quickly if the launch bases are farther away, if aircraft must hold for timing, if there are multiple refueling tracks, or if support aircraft also need gas.
For the final question, there are two answers. If the question is direct consumable cost, munitions probably dominate. Even JDAM tailkits are tens of thousands of dollars before counting the bomb body and logistics, while longer-range standoff weapons can be in the million-dollar class. A package of 60 to 120 precision weapons can easily outrun a few million dollars of jet fuel.
If the question is operational logistics, the answer is probably the support aircraft and refueling architecture. The strike aircraft are the visible part, but the mission depends on tankers, command-and-control, surveillance, electronic warfare, timing, routing, protection, and recovery.
Post-check reflection
Matt's reflection
I think I was pretty much where I needed to be for this one. My intuition for the cost of the missiles was probably low, but close enough to get me a correct Fermi answer. My intuition about the number of missiles per target was OK, and the number of aircraft might have been a slight overestimate.
I am happy I was able to get close on the fuel consumption estimate per jet using just my guess for their mass, average velocity, and lift-to-drag ratio. That is an improvement over other recent news items. My aircraft mass guess was about double the actual number, which is fine for Fermi work. I assumed 50% fuel efficiency but it was closer to one-third. I also doubled the per-liter fuel cost. All of that still put me in the right ballpark, and it was close enough to get me to the right answer for the bigger-picture cost question.
Ultimately, the majority of the direct mission cost sits in the munitions, and my ratio of 7:1 when munition costs are compared to fuel costs is a reasonable one. I understood that the smart long-range weapons were an enormous cost and were the main contributor to the cost of these types of missions, but this really firms up that intuition.
Recommended memory peg
Remember a strike fighter on a demanding mission can be treated as roughly 10^4 liters of fuel per sortie, and a tanker sortie can be treated as roughly 10^5 pounds of useful transferable fuel. For strike packages, estimate strike sorties first, then multiply aircraft-hours by two or three to account for support.
Reader results
Bars show how submitted estimates sort into the answer choices from the gut-check prompt.