HENSYNTH MTOW and empty mass in screening

Why weight sits at the top of the run report

On the Requirements run report, MTOW and empty mass appear first among metrics because stall speed, climb, range, endurance, and takeoff distance all scale with weight and wing area. HENSYNTH’s help modal for MTOW states the intent plainly: the mass the rest of the screening is sized against. A lighter guess would make every later number look too easy.

What MTOW means in the product

Maximum takeoff mass is empty mass plus payload, crew, and battery or fuel as the architecture requires. The engine does not treat MTOW as a single independent input you type on Requirements — it is a prediction from the build-up for the aircraft you saved. Payload and battery caps from Requirements feed that build-up; MTOW is what comes out.

The formula text in the ? modal describes an iterative loop: start from a seed related to payload, rebuild component masses until MTOW changes less than a small threshold. That is screening fidelity, not a weighed aircraft on scales.

Empty mass and component groups

Empty mass sums wing, tails, fuselage, landing gear, propulsion, systems, avionics, and furnishings. Payload, crew, battery, and fuel are excluded from empty mass so you can see how much structure and systems consume the MTOW budget.

• Electric UAV path — used for electric architectures and aircraft below the crossover mass in the engine rules.
• Heavier general-aviation path — Raymer-style build-up when mass and architecture cross the fuel-aircraft branch, using cruise dynamic pressure among inputs.

Open the empty mass ? modal on your run for the exact branch your project took. Do not quote generic empty fractions from this blog — read the stored values on your project.

Link to synthesis “minimum MTOW” style

When you synthesize candidates, the minimum MTOW style searches wing loading and related knobs to reduce predicted takeoff mass while still attempting to close requirements. After you apply a candidate with Use this aircraft, Run screening again so MTOW and empty mass on the requirements report reflect the new geometry and sizing choices.

Screening only

Component weights at conceptual design are historically uncertain. HENSYNTH returns consistent handbook-style masses for trade studies. They are not as-built weights, not structural test results, and not basis for certification mass and balance reports without your own substantiation.

In simple words: what this page is for

How HENSYNTH builds MTOW and empty mass for conceptual screening — component groups, electric UAV vs heavier GA paths, and why weight drives every later metric.

This lesson exists because aircraft teams often jump to heavy CFD before the mission is even closed. HENSYNTH MTOW and empty mass in screening keeps the focus on conceptual screening you can explain in review.

Why the topic matters

Engineers lose time when a title sounds clear but the page only sketches the idea. This article expands HENSYNTH MTOW and empty mass in screening so you can answer three questions without jargon: what is the idea, when do you use it, and how do you check it in a HENDOI product.

Read the sections above for the core definitions. Use the steps below to move from reading into a real project trail you can share with a teammate.

How to apply this in HENDOI

In practice: open HENSYNTH after you sign in, set or confirm geometry, write mission targets on Requirements, Run screening, then read PASS / FAIL with margins. Use Mission, Performance, Trades, Optimize and Reports only after the screening snapshot exists. Numbers come from stored runs — the product does not invent missing values.

If you still need the wing section itself, finish that work in HENFOIL first, then continue the aircraft in HENSYNTH. One HENDOI account covers both. Plans stay Student USD 9, Professional USD 29 and Team USD 89.

What this page will not claim: HENSYNTH is conceptual and preliminary screening. It is not wind-tunnel data, not certification CFD, and not a compliance certificate for an authority. PASS / FAIL means requirement-versus-prediction inside the product.

Checklist before you leave this page

• Can you state the idea of HENSYNTH MTOW and empty mass in screening in one sentence?
• Do you know which product owns the next action — HENSYNTH or HENFOIL?
• Will every number you keep carry a method label or a stored-run source?
• If you are new here, have you opened Register or Login?

Related reading on this site

• HENSYNTH candidate cards, Use this aircraft, and CAD
• HENSYNTH compliance matrix: PASS, FAIL, and margin
• HENSYNTH download and share technical reports
• HENSYNTH Geometry page: wing, fuselage, and tails
• All HENDOI blog articles
• HENSYNTH product page
• HENFOIL product page
• Pricing — Student, Professional & Team
• FAQ
• Login · Register now