Diamond DA42 vs Diamond DA40

The Diamond DA40 (single-engine, ~150 kt) and DA42 Twin Star (twin-engine, ~170 kt) are the single and twin members of the Diamond composite-diesel line — same design language and Austro AE diesel philosophy, but one engine vs two.

Live Market Snapshot

Current asking-price market, aggregated across multiple marketplaces · refreshed daily

Diamond DA42
For sale now
46
Median asking
$699,900
Range
$520,774–$1,100,160
Listed on 2+ marketplaces
20
Source marketplaces
7
Model years available
2005–2026
Diamond DA40
For sale now
85
Median asking
$424,858
Range
$184,562–$670,700
Listed on 2+ marketplaces
39
Source marketplaces
10
Model years available
2000–2026

Live data from AeroGurus, aggregated daily across the used-aircraft market. Figures are current asking prices, not appraisals — confirm with a pre-buy inspection.

Safety Record

Absolute counts scale with fleet size — the most-produced types log more events without being less safe. Compare the % fatal.

NTSB (1982–now)Diamond DA42Diamond DA40
All events710
Serious10
Fatal03
Fatalities05
% Fatal0%30%
View full Diamond DA42 NTSB record →View full Diamond DA40 NTSB record →

Full Specs Comparison

Swipe to see all specs
Spec / Model Diamond DA42 Diamond DA40
Diamond DA42
View 44 listings →
Median $699,900
 Diamond DA40
View 81 listings →
Median $424,858
Price Range $520,774 – $1,100,160 $184,562 – $670,700
Category Multi Engine Piston Single Engine Piston
Model Specifications
Seats 4 4
Horsepower — 180 HP
Cruise Speed 170 kts (315 km/h) 135 kts (250 km/h)
Range 1,050 nm (1,945 km) 635 nm (1,176 km)
Service Ceiling 18,000 ft (5,486 m) 16,400 ft (4,999 m)
Max Gross Weight 3,935 lbs (1,785 kg) 2,535 lbs (1,150 kg)
Useful Load 940 lbs (426 kg) 780 lbs (354 kg)
Fuel Capacity 50.0 gal (189 L) 40.0 gal (151 L)
Fuel Burn 12.0 GPH (45 L/h) 9.5 GPH (36 L/h)
TBO 1,800 hrs 2,000 hrs
Overhaul Cost $28,000 $25,000
Annual Fixed $20,000 $16,000
Hourly Variable $150 $120
Engines 2 x Diesel 1 x Piston

Cost of Ownership

Estimate

Diamond DA42

Fuel$66/hr
Variable$150/hr
Annual Fixed$20,000/yr
Total (200 hrs/yr) $50,000/yr

Diamond DA40

Fuel$52/hr
Variable$120/hr
Annual Fixed$16,000/yr
Total (200 hrs/yr) $40,000/yr

Which Should You Buy: Diamond DA42 or Diamond DA40?

Bottom line: Choose the DA40 for single-engine operating economics, the class-leading four-seat safety record and lower acquisition cost. Step up to the DA42 when you need twin-engine redundancy (IFR, overwater, multi-engine rating) and ~20 kt more cruise — at roughly double the fuel burn and twin-engine maintenance. 🚨 On DA42, verify Austro AE300 (not legacy Thielert) engines.

Pick the DA42 if…

  • Faster cruise — 170 kts vs 135 kts.
  • Longer range — 1050 nm vs 635 nm.
  • Newer design — production from 2004 vs 2000.

Pick the DA40 if…

  • Budget matters — from $184,562 vs $520,774, you save ~$336,212.
  • Lower operating cost — ~$120/hr vs $150/hr.
  • More inventory — 81 listings vs 44.

Auto-generated from current market data and published specs. Confirm with a pre-buy inspection and professional appraisal.

Frequently Asked Questions

Which is better, Diamond DA42 or Diamond DA40?
It depends on your mission and budget. The DA42 cruises at 170 kts with 1,050 nm range. The DA40 cruises at 135 kts with 635 nm range. Review the specs table above to find which fits your flying profile.
How do prices compare?
Diamond DA42: from $568,000. Diamond DA40: from $580,000. Prices vary by year, hours, avionics, and condition. Always get a pre-buy inspection.
What's the difference between Diamond DA42 and Diamond DA40?
Cruise: 170 vs 135 kts. Range: 1050 vs 635 nm.
Which is cheaper to operate per hour?
DA42: about $150/hr variable cost. DA40: about $120/hr variable cost. Variable cost includes fuel, reserves and overhaul accruals. Annual fixed costs (hangar, insurance, annual inspection) add to the total.
Which has more seats and useful load?
DA42: 4 seats / 940 lb useful load. DA40: 4 seats / 780 lb useful load. Useful load = max gross weight minus empty weight; it determines how much fuel plus payload you can carry.
How does maintenance compare — TBO and overhaul cost?
DA42: 1,800-hour TBO, overhaul ~$28,000. DA40: 2,000-hour TBO, overhaul ~$25,000. Reaching the time-between-overhaul (TBO) triggers a mandatory engine/airframe rebuild that affects resale value.
Disclaimer: All prices and cost estimates are from third-party sources for informational purposes only. Always obtain professional appraisal and inspection before purchase.
Prices updated daily · Data: FAA Registry, NTSB · About our data