Conventional tail (low-mounted stabiliser and single fin) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/conventional-tail/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
Catalog version: 2026-10-20

Sizes: see table below
- A conventional tail mounts the horizontal stabiliser low on the fuselage with a single fin above it; Arnedo calls it structurally compact and aerodynamically efficient, the standard for aircraft with under-wing engines.
- It is easy and cheap to build and hard to stall, but it sits in the wing's downwash and the propeller slipstream (Bhattacharya et al.; Kitplanes). On single-engine tractor aircraft the slipstream over a low tail helps raise the nosewheel, which a T-tail loses (Kitplanes T-Tails).
- Size it with the tail volume coefficient: Raymer-type tables give Vh 0.50/Vv 0.04 for homebuilts and 0.70/0.04 for GA singles (HAW Hamburg Table 2.1).
- Used on: Cessna 172, Beechcraft A36 Bonanza, Boeing 777, Airbus A320, Piper Cherokee Six (PA-32).
- The file is a reference example built by Xem Studio from the numbers above. Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

parameter  value or range  source
Homebuilt Vh / Vv  0.50 / 0.04  HAW Hamburg Table 2.1
GA single Vh / Vv  0.70 / 0.04  HAW Hamburg Table 2.1
Horizontal vs vertical tail arm  horizontal about 5% longer  Scholz 2021
Piper J-3 Sh/Sw, Sv/Sw  13.7%, 5.7%  EAA62 (Pazmany)
Reference build  Sh 40,000 mm^2 (400 x 100), Sv 16,000 mm^2 (140 x 114), arm 500 mm on a 1000 x 200 mm wing  computed (Vh 0.50, Vv 0.04)

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- LibreTexts (Arnedo, Fundamentals of Aerospace Engineering): 2.2.3 Empennage — web — Publisher's page; dimensions are facts — https://eng.libretexts.org/Bookshelves/Aerospace_Engineering/Fundamentals_of_Aerospace_Engineering_(Arnedo)/02%3A_Generalities/2.02%3A_Parts_of_the_aircraft/2.2.03%3A_Empennage
- engrXiv (Bhattacharya et al., ICMMM 2023): Design and Computational Analysis of Y-tail Configuration for Maritime UAV — web — Publisher's page; dimensions are facts — https://engrxiv.org/preprint/download/6582/10812/9153
- Kitplanes (B. Wainfan): Design Process: T-Tails (2022) — web — Publisher's page; dimensions are facts — https://www.kitplanes.com/design-process-t-tails/
- HAW Hamburg (Aircraft Design and Systems Group): Empennage sizing: tail lever arm as % of fuselage length (thesis; Table 2.1 typical tail volume coefficients) — web — Publisher's page; dimensions are facts — https://www.fzt.haw-hamburg.de/pers/Scholz/arbeiten/TextMcDavid.pdf
- INCAS Bulletin / HAW Hamburg (D. Scholz): Empennage sizing with the tail volume complemented with a method for dorsal fin layout (2021) — web — Publisher's page; dimensions are facts — https://www.fzt.haw-hamburg.de/pers/Scholz/Aero/AERO_PUB_INCAS_TailVolume_Vol13No3_2021.pdf
- EAA Chapter 62 (Stan Hall, from Pazmany 'Light Airplane Design'): How Big The Tail — web — Publisher's page; dimensions are facts — https://eaa62.org/technotes/tail.htm

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/conventional-tail/index.json
API: https://xemstudio.com/api/geometry?object=conventional-tail