> ## Documentation Index
> Fetch the complete documentation index at: https://docs.skyvexsoftware.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Landing Score & Fuel Efficiency
> How the Landing Analyser turns a touchdown into a score — the six categories, their bands, how the composite is weighted, and a full explanation of the Fuel Efficiency category and the numbers shown on its card.
The Landing Analyser plugin grades every landing out of 100. That grade is a **weighted average of six categories**, each scored 0–100 on its own. This page explains what each category measures, the exact bands it uses, and how the composite is assembled — with a detailed section on **Fuel Efficiency**, which is the category pilots ask about most.
For how the landing *rate* itself is measured (the curve fit through gear height, not a single simvar), see [Landing Rate Detection](/guide/landing-rates).
## The composite score
Each category produces a 0–100 score. The composite is the weighted average of the categories that could actually be evaluated:
| Category | Default weight | Measures |
| ------------------ | -------------- | ------------------------------------------------- |
| Landing Rate | 30 | Descent rate at the moment of touchdown |
| Approach Stability | 20 | How steady V/S and bank were on short final |
| G-Force | 15 | Peak vertical g at touchdown |
| Bounce Quality | 15 | Number and height of bounces |
| Rollout | 10 | Percentage of the landing distance available used |
| Fuel Efficiency | 10 | Actual block burn against the planned block burn |
**Everything on this page is the Stratos default.** Your virtual airline can
change the weights and several of the band sets in its Landing Analyser plugin
configuration, so the numbers you see may not match the ones documented here.
If a score doesn't line up with this page, check with your VA staff first.
### What your VA can change
| Setting | Config key | Configurable |
| ----------------------------- | ------------------- | ------------ |
| Category weights (all six) | `scoring_weights` | Yes |
| Landing-rate bands | `landingRate_bands` | Yes |
| Landing-rate "too soft" floor | `landingRate_floor` | Yes |
| G-force bands | `gforce_bands` | Yes |
| Rollout utilisation bands | `rollout_bands` | Yes |
| Bounce bands | — | Fixed |
| Approach-stability bands | — | Fixed |
| Fuel-deviation bands | — | Fixed |
| Stability-gate thresholds | — | Fixed |
A weight can be set to zero to remove a category from the composite entirely, and any band set can be reshaped to match the airline's own standards. Invalid configuration is ignored rather than applied: if a band set fails validation the plugin logs a warning and falls back to the defaults documented here, so a typo in an airline's config can never produce nonsense scores.
VA administrators: these live in your airline's Landing Analyser plugin configuration on the Skyvex admin side, alongside the rest of your plugin settings.
### Skipped categories
A category that can't be honestly evaluated is **skipped**, not scored zero. Its card reads "Not scored" and shows an em dash, and its weight is dropped from the composite and redistributed across the remaining categories. This happens when:
* **Rollout** — the arrival runway couldn't be matched confidently, so there's no landing distance available to measure against.
* **Approach Stability** — too few samples on short final (tracking started low, a sim hiccup, an older shell build).
* **Fuel Efficiency** — no SimBrief flight plan was found for the flight, so there's no planned burn to compare against.
A missing flight plan should never tank an otherwise good landing, which is why the category disappears instead of scoring zero.
### Verdict labels
Every category score, and the composite, maps to a label:
| Score | Verdict |
| ------ | ------------- |
| 90–100 | Excellent |
| 80–89 | Good |
| 70–79 | Average |
| 50–69 | Below Average |
| 0–49 | Poor |
## Fuel Efficiency
### What the two numbers on the card mean
The Fuel Efficiency card shows two figures, and they measure different things:
* **The large number (e.g. `+1,365 kg`)** is the **total fuel you burned on the flight**, in your preferred weight unit (Settings → Weight Unit). It is not a variance, a saving, or a difference from plan. The leading `+` is a display prefix on that card only; read it as "1,365 kg of fuel used".
* **The small number in the corner (e.g. `85 pts`)** is the category score, which is what actually feeds your composite.
If you want the plan-versus-actual figures, open **Detailed Data → Rollout & Fuel** in the report. That panel shows the three numbers the score is built from:
| Row | Meaning |
| --------------- | -------------------------------------------------------------------------- |
| Fuel on landing | Fuel remaining in your tanks at touchdown |
| Plan remaining | SimBrief's planned fuel at destination (`plan_landing` from the OFP) |
| Fuel variance | Fuel on landing minus Plan remaining. Positive means you landed with extra |
### How the score is calculated
The score is based on **percentage deviation from the planned burn**, not on raw pounds.
Stratos captures your fuel at the start of the flight (at push back by default — your VA can configure this to take-off instead), and again at touchdown. The difference is your actual burn. The planned burn is derived from your starting fuel and SimBrief's planned arrival fuel:
```
actual burn = starting fuel − fuel on landing
planned burn = starting fuel − SimBrief plan remaining
deviation % = (actual burn − planned burn) / planned burn × 100
```
Positive deviation means you burned **more** than planned (over-burn). Negative means you burned **less** (under-burn).
Because starting fuel is normally captured at push back, both sides of that comparison are **block** figures: the planned burn includes SimBrief's taxi allowance, and your actual burn includes your real taxi. If your VA has set fuel capture to take-off instead, both sides become enroute-only figures. Either way the comparison is like for like.
### The bands
Over-burn is penalised much harder than under-burn. These bands are fixed and not VA-configurable, though the **weight** the category carries is:
| Deviation | Score | Meaning |
| -------------------------- | ----- | ------------------------------------------------ |
| Under-burn 15% or more | 85 | Well under plan — the plan is treated as suspect |
| Under-burn 5% to 15% | 95 | Comfortably under plan |
| Within 5% under to 2% over | 100 | On plan |
| Over-burn 2% to 5% | 80 | Slightly heavy |
| Over-burn 5% to 10% | 55 | Noticeably heavy |
| Over-burn 10% to 20% | 25 | Well over plan |
| Over-burn 20% or more | 5 | Far over plan |
The asymmetry is deliberate. Burning more fuel than planned usually reflects the profile actually flown: heavy, slow, low, or a lot of manoeuvring. Burning less usually means the flight plan over-padded, which is the planner's doing rather than the pilot's, so the penalty stops early.
**85 is the floor for under-burning, not a failing grade.** There is no band
below it on the under-burn side. However far under plan you land, the worst
Fuel Efficiency can score is 85, and internally that result is flagged as
"planned burn may be off" rather than as a piloting fault. At the default
weight of 10, the difference between 85 and 100 moves your composite score by
about 1.5 points.
### Why a consistent 85 is common
A steady 85 means you keep landing with 15% or more of the planned burn still in the tanks. That is usually the flight plan rather than the flying, and there are a few normal causes:
* **Unburned taxi allowance.** SimBrief's default taxi fuel is generous, and with fuel captured at push back that allowance sits inside the planned burn. If your taxi out is short, the leftover counts as an under-burn. On a short sector this alone can be 15% of the whole planned burn, because the planned burn is small to begin with.
* **Fuel loaded above the OFP figure.** The planned burn is derived from what you actually started with, so any extra fuel you tanker above SimBrief's ramp figure inflates the planned burn and reads as an under-burn. Rounding up at the fuel truck, an EFB that loads by percentage, or a VA loadsheet that adds its own margin will all do this.
* **The aircraft burns less than the SimBrief profile.** Airframe profiles are averages. If the aircraft or mod you fly is more efficient than the profile you selected in SimBrief, every flight will read as an under-burn.
* **A better-than-planned profile.** Direct routings, no holding, favourable step climbs, and no ATC vectoring all put fuel back in the tanks that the plan assumed you would burn.
### Aiming for 100
To sit in the 100 band your block burn needs to land between 5% under and 2% over the plan. In practice that means tightening the plan rather than changing how you fly:
1. Load **exactly** the SimBrief ramp figure, not a rounded-up number.
2. Make sure the SimBrief airframe profile matches the aircraft and mod you actually fly.
3. Set the cost index, cruise levels, and route in SimBrief to what you intend to fly.
4. Bring SimBrief's taxi fuel in line with your usual taxi time, especially on short sectors.
If you have done all of that and still land 15% up, the plan is over-padded for the aircraft you fly, and 85 is the score the model is designed to give.
Because the only planned figure the OFP gives us that survives contact with
the flight is the fuel expected in the tanks on arrival. Comparing your actual
arrival fuel against that, and working the burn back from your real starting
fuel, means the comparison holds even when you load a different amount of fuel
to the plan, divert, or fly a different routing. The trade-off is that extra
fuel loaded and fuel not burned look identical at touchdown, which is why the
under-burn penalty is capped.
## Landing Rate
The touchdown descent rate, scored on magnitude. See [Landing Rate Detection](/guide/landing-rates) for how the rate itself is derived. **Bands and floor are VA-configurable** (`landingRate_bands`, `landingRate_floor`); the defaults are:
| Rate (fpm) | Score |
| ---------- | ----- |
| Under 100 | 65 |
| 100 to 200 | 100 |
| 200 to 350 | 85 |
| 350 to 500 | 70 |
| 500 to 650 | 40 |
| 650 to 800 | 10 |
| Over 800 | 0 |
Anything softer than 100 fpm scores 65 rather than 100. A greaser delays weight transfer to the gear, which delays spoiler and reverser deployment, so it is not the target. VAs can move the floor or set it to zero to disable the rule.
## G-Force
Peak vertical g at touchdown. **Bands are VA-configurable** (`gforce_bands`); the defaults are:
| Touchdown g | Score |
| ----------- | ----- |
| Up to 1.30 | 100 |
| Up to 1.45 | 85 |
| Up to 1.60 | 70 |
| Up to 1.80 | 40 |
| Up to 2.00 | 10 |
| Above 2.00 | 0 |
G-force is scored on its own, but it has limited say over the **verdict** on the landing. Sim gear-strut models routinely throw a single-frame g spike on an otherwise smooth touchdown, so g can only worsen the vertical-speed verdict by one band, and can never on its own drive the verdict to the worst band.
## Bounce Quality
Fixed bands, not VA-configurable.
| Bounces | Score |
| ------------------------ | ----- |
| None | 100 |
| One, under 10 ft AGL | 70 |
| One, 10 ft AGL or higher | 50 |
| Two | 30 |
| Three or more | 10 |
## Approach Stability
Measured as how **steady** you were, not where you happened to be at one instant. Stratos takes the standard deviation of vertical speed and of bank angle across the approach window (airborne, at or below 1,000 ft AGL, excluding the last 3 seconds before touchdown so the flare doesn't count against you), bands each one, and takes the **worse** of the two. Fixed bands, not VA-configurable.
| σ vertical speed (fpm) | Score | | σ bank (degrees) | Score |
| ---------------------- | ----- | - | ---------------- | ----- |
| Under 100 | 100 | | Under 2 | 100 |
| Under 200 | 80 | | Under 5 | 80 |
| Under 400 | 50 | | Under 10 | 50 |
| Under 700 | 25 | | Under 15 | 25 |
| 700 or more | 0 | | 15 or more | 0 |
Taking the worse axis means you can't hide a porpoising descent behind level wings, or wing-rock behind a steady rate. Fewer than five samples in the window and the category is skipped.
## Rollout
Scored on how much of the runway you used, not on a fixed distance, so a 1,800 m rollout at a 4,000 m runway is treated very differently to the same rollout at a 2,000 m one.
```
LDA = runway length − displaced threshold
distance used = touchdown distance from threshold + rollout distance
utilisation % = distance used / LDA × 100
```
**Bands are VA-configurable** (`rollout_bands`); the defaults are:
| Runway used | Score |
| ----------- | ----- |
| Up to 45% | 100 |
| Up to 65% | 80 |
| Up to 85% | 55 |
| Up to 90% | 25 |
| Up to 100% | 5 |
| Over 100% | 0 |
If the arrival runway couldn't be matched confidently, the category is skipped and the card shows your raw rollout distance instead of a misleading percentage.
## The stability gate
Separately from the six categories, Stratos evaluates a **50 ft stabilised-approach gate** against class-aware thresholds:
| Aircraft class | Max V/S | Max IAS over Vref | Max bank |
| -------------- | -------- | ----------------- | -------- |
| Widebody | 800 fpm | 10 kt | 5° |
| Narrowbody | 1000 fpm | 15 kt | 7° |
| Regional | 1200 fpm | 20 kt | 8° |
Failing the gate shows an "Unstable approach" badge on the report. It is informational and **does not change your score**. Vref comes from SimBrief, so with no flight plan filed the gate isn't evaluated and the badge is hidden.
## Frequently asked questions
No. That figure is the total fuel you burned on the flight. The `+` is just a
display prefix on that card. For plan-versus-actual, look at the "Fuel
variance" row under Detailed Data → Rollout & Fuel.
No SimBrief flight plan was found for that flight, so there was no planned
burn to compare your actual burn against. The category is dropped from the
composite entirely and its weight is shared out across the other categories,
so it doesn't cost you anything.
Most likely nothing. 85 is the lowest score an under-burn can produce, and it
means you landed with 15% or more of the planned burn still on board. The
usual causes are an unburned taxi allowance (which is a big share of a short
sector's planned burn), fuel loaded above the OFP ramp figure, or an airframe
profile in SimBrief that is thirstier than the aircraft you actually fly.
Tightening the plan moves the score; flying differently generally won't.
The weights, the landing-rate bands and floor, the g-force bands, and the
rollout bands are all configurable per airline in the Landing Analyser plugin
configuration. The bounce, approach-stability, and fuel-deviation bands are
currently fixed.
Landing Rate carries the largest default weight at 30, so it moves the
composite most. Everything else is 20 or below. If a low composite doesn't
match a category card you're looking at, check whether another category was
skipped, because its weight is redistributed and that changes how much every
remaining category counts.