Piper PA-31 Navajo

The Piper PA-31 Navajo is the airplane the "Navajo" name originally belonged to — a six-to-eight-place, low-wing, retractable-gear cabin-class twin that first flew on 30 September 1964 under Piper's internal project name "Inca," and entered FAA certification under TC A20SO on 24 February 1966. Deliveries began in 1967. It is, in effect, a scaled-up PA-30 Twin Comanche: the same low-wing, laminar-flow-adjacent design language, stretched to carry a cabin instead of four seats and two 310 hp turbocharged Lycoming TIO-540s instead of two 160 hp IO-320s.

This page describes the base, un-stretched PA-31 Navajo — the airplane Piper actually certificated under Model I of TCDS A20SO, at a 6,500 lb gross weight, with two same-rotation (non-counter-rotating) TIO-540-A2C engines. It is a separate page from the PA-31-350 Chieftain, which Piper introduced in September 1972 by stretching this airframe's fuselage two feet, adding counter-rotating engines and 350 hp a side, and raising gross weight to 7,000 lb. The split decision, and the numbers behind it, are recorded at the bottom of this page — read it before assuming this is a formatting choice rather than a researched one.

Piper built 1,785 PA-31s (against 1,825 PA-31-350 Chieftains) across the type's production life. The TCDS's own eligible-serial range for Model I runs all the way to S/N 31-8312019 — encoded as roughly 1983 production — so the base Navajo was not simply superseded by the Chieftain in 1972; Piper kept selling both side by side for a decade, with the Chieftain steadily taking the larger share of the volume. Anecdotally (not independently verified this session), most surviving, actively-marketed base Navajos are pre-1973 airframes, since that is when a buyer wanting more airplane started gravitating to the Chieftain instead. Say so, do not assert a hard year cutoff this session cannot back with a document.

The Navajo was Piper's first entry into the true cabin-class twin market, and it found the same customers the Chieftain later dominated: small feeder airlines (West Coast Airlines flew it in scheduled passenger service from 1967, calling it the "MiniLiner"), air-taxi and charter operators, and corporate flight departments wanting IFR-capable, six-to-eight-seat lift without stepping up to a turboprop. Two smaller variants share this certificate and this page's Variants table rather than getting pages of their own: the PA-31-300 (naturally aspirated, only 14 built) and the PA-31-325 Navajo C/R (325 hp, counter-rotating, introduced 1974-75 alongside the Chieftain). The pressurized PA-31P Pressurized Navajo is not on this certificate at all — a lead (not yet independently confirmed this session) points to a separate TC, A8EA — and is out of scope for this page exactly as it already was for the Chieftain's.

Notes:

• Two airspeed blocks exist within the base Navajo itself. The earliest ~700 airframes (S/N 31-2 through 31-711) carry Va 163 kt and the earlier TIO-540-A1A/A1B/A2A/A2B engines; every serial from 31-712 on (including the entire high-serial continuation block, 31-7300901 through 31-8312019) carries Va 159 kt and the TIO-540-A2C. This page's frontmatter describes the majority (later) block, per the certificate's own serial-eligibility count.
• The 6,500 lb gross weight itself has a sub-history: Piper's original February 1966 approval was for 6,200 lb; a July 1966 reissue raised it to 6,500 lb takeoff (6,200 lb landing on the earliest serials, 6,500 lb both takeoff and landing from S/N 31-712 on). The certificate's Note 3 records this.
• Baggage: 350 lb standard (fuselage-only); an optional nacelle-locker installation raises this to 650 lb, the same trade Piper later offered on the Chieftain (700 lb standard, 500 lb with optional nacelle FUEL tanks instead of baggage lockers).

No POH was obtained for this airplane. A type certificate publishes no cruise speed, no fuel burn, no range, no climb rate and no stall speed — see docs/CATALOG-FIELD-SOURCES.md. The handbooks that would answer those questions are named by part number right on the certificate (PAC Report 1702, POH 2045, POH+AFM LK-1206 for the majority serial block) but none were reachable this session as a native-text or scanned PDF — see this page's validator_exempt block for exactly what was searched.

A 2026-09-11 pass sourced the performance figures below from two press sources instead. cruise_speed_ktas (185 kt), cruise_percent_bhp (68) and fuel_burn_gph (37, the midpoint of a stated "36 to 38 gph" range) come from Piper Flyer Association's magazine ("Flying the PA-31," Michael Leighton, November 2005) — a charter operator's real-world report on his own 1970 base PA-31-310 Navajo, ONE source at ONE stated power setting (32 in. Hg / 2,200 rpm, "about 68 percent"), the condition rule 3 requires. The live piperflyer.com page returns a Cloudflare bot challenge to a direct fetch; the same page's text was retrieved via a Wayback Machine snapshot instead — still the page's own literal words, not a summary. fuel_burn_gph is COMBINED (both engines), the field that unblocks this page's cost model.

rate_of_climb_fpm (1,395 fpm), service_ceiling_ft (26,300 ft), vs1_kias/vs0_kias (66/61 kt, explicitly labeled clean vs. landing configuration) and empty_weight_lbs/useful_load_lbs (4,003/2,497 lb) come from AOPA's own "Piper Navajo/Chieftain" aircraft fact sheet — its "1980 PA-31-310T Piper Navajo C" column matches this page's TIO-540-A2C engine and 6,500 lb gross weight exactly. That source's own "Avg. Fuel Burn at 75% power" cell is stated as "Unknown," so it does not help fuel_burn_gph. service_ceiling_ft now holds this POH-type climb-derived ceiling rather than the certificate's own Maximum Operating Altitude (24,000 ft, a different, legal pressure-altitude limit — still true, now discussed only in prose below rather than stored in this field, per CATALOG-FIELD-SOURCES.md's caution that the two are different questions).

Neither source gives range_nm at a stated setting — the Piper Flyer article mentions "nearly 1,400 miles of range" only as a general full-fuel remark, not tied to the 68%-power row — so it is not stored, per rule 3.

What the certificate DOES establish, reliably: Vne 236 kt, Vno 188 kt, Va 159 kt (majority block), Vfe 130 kt (40° flaps, all serials), Vmc 74 kt (not a stored frontmatter field on this schema, noted here in prose), a 24,000 ft certificated maximum operating altitude, and 187 gallons of usable fuel out of 192 total (NOTE 1's unusable-fuel arithmetic — see the passage for the exact calculation).

One genuinely useful cross-check, not stored as a figure. Wikipedia's infobox for this exact airplane (citing Jane's All The World's Aircraft 1976-77) independently arrives at "190 gal total, 187 gal usable" — matching this page's TCDS-derived 187 usable gallons almost exactly, via completely different arithmetic (a published spec sheet, not NOTE 1's per-serial unusable-fuel subtraction). That is real corroboration of the fuel figure. The same infobox's performance figures (238 mph / 207 kt econ cruise at 20,000 ft, 1,165 mi / 1,012 nm range, 73 mph / 63 kt stall flaps-down, 1,445 fpm climb, 26,300 ft service ceiling) are a single secondary source and are NOT stored on this page — runbook rule 29 requires three independent sources agreeing within 5% before a secondary source may fill a performance field, and this page has exactly one. They are recorded here as a lead for a future research pass, not as evidence.

A NASA technical report on a 1978 Chieftain crash (NASA_NTRS 19790025001, "Comparative analysis of PA-31-350 Chieftain (N44LV) accident and NASA crash test data") independently states the Chieftain's "gross weight limit of 3200 kg (7000 lb) and a stall speed of 38 m/s (74 knots)" — the gross weight matches the TCDS exactly (a genuine corroboration, for the Chieftain, not this page), but the document is a badly-OCR'd 1979 scan (garbled text throughout, e.g. "NavaJo," "_amote_s") and is not saved as a citation-quality passage; it backs nothing stored on either PA-31 page.

Now computable. AOPA's fact sheet gives Standard Empty Weight 4,003 lb for the matching TIO-540-A2C / 6,500 lb column, and its own stated Max. Useful Load (2,497 lb) reconciles exactly with this page's TCDS gross weight: 6,500 - 4,003 = 2,497. (Wikipedia/Jane's separately states 3,930 lb for this exact airplane — a single secondary source, 73 lb lighter than the AOPA figure, not stored but noted here as a lead.) Fuel is the other number on this side of the ledger, and it is certificate-verified: 187 usable gallons (1,122 lb at 6.0 lb/gal), against the Chieftain's 182 usable gallons (1,092 lb) — the two airframes carry almost identical fuel despite the Chieftain's heavier gross weight and longer cabin, which is itself a useful, TCDS- verified finding: fuel capacity is not what separates these two airplanes. What separates them is cabin length, seat count, baggage capacity and — most operationally — whether the airplane has a critical engine at all.

With full 187-gallon fuel (1,122 lb) and the 2,497 lb useful load, that leaves 1,375 lb for people and cargo with full tanks — roughly five FAA- standard 170 lb occupants (850 lb) plus 525 lb of baggage/cargo, comfortably inside the 350 lb standard baggage limit if spread across passengers and compartment. A buyer loading all 6-8 seats will trade fuel for payload well before running the tanks dry, exactly the tradeoff every cabin-class piston twin in this catalogue faces.

Panel history tracks the Chieftain's closely — both airframes shared Piper's factory avionics options across the same production decades. See the Chieftain page's Avionics Ecosystem section for the legacy-to-glass upgrade path (Bendix/King Silver Crown baseline, Garmin G500/GTN mid-tier, GFC 600 full-glass with Smart Rudder Bias); nothing in this session's research distinguishes the two airframes' avionics options, and duplicating that section here would not add anything true that isn't already said there.

The Colemill/Mike Jones Panther conversion (re-engined with individual-magneto TIO-540-J2B, four-blade Q-Tip propellers, optional winglets — see the Chieftain page) is documented specifically for the PA-31-350 and PA-31-325. Mike Jones Aircraft's STC coverage explicitly extends to the PA-31 as well (per Wikipedia's variant summary: "continues to convert PA-31, PA-31-325 and PA-31-350 variants with Colemill-developed features") but this session found no PA-31-specific performance deltas or pricing separate from the already-documented Chieftain conversion — not independently verified, noted as a lead only.

Shares the Chieftain's TIO-540 engine family and much of its parts ecosystem — see that page's Maintenance & Support section for parts-availability and mechanic-familiarity detail, which this page inherits by reasoning (same engine family, same-era airframe, same supply chain of Piper/Aircraft Spruce/Wag-Aero and the same dual-magneto TIO-540 reliability profile) rather than independent sourcing this session.

Engine reserves: at $58,000 per engine (reference/engine-overhaul-pricing.md's TIO-540 specialty-shop tier — the same figure the Chieftain page uses, per runbook rule 6's instruction not to re-research per airplane) and the 1,800-hour TBO this session confirmed from Lycoming's own Service Instruction 1009BF, that is $32.22/hr per engine, or $64.44/hr for the pair — the same per-hour reserve as the Chieftain, since both airplanes' engines share the identical TBO and the identical reference-file overhaul price.

See Aircraft Valuation Methodology. This page's price is MARKET ASKING data, not a Vref or Aircraft Bluebook figure — this catalogue has no subscription to either guide, and rule 27 allows market asking as a fallback only when labeled as exactly that. The prior session's attempt (bot protection and required JavaScript blocking every channel) found nothing; a fresh check on 2026-09-11 through a real browser session did not hit the same wall.

Controller.com's own model field separates the base Navajo from its siblings, which matters because "Piper Navajo" listings otherwise mix four different airplanes: the base PA-31 this page describes, the stretched PA-31-350 Chieftain (a separate page), the counter-rotating PA-31-325 C/R (a Variants-table row on this page), and the pressurized PA-31P (a different certificate entirely, out of scope). Controller buckets these as "PIPER NAVAJO," "PIPER NAVAJO CHIEFTAIN," "PIPER NAVAJO CR" and "PIPER P-NAVAJO" respectively — only the first bucket is used here.

Six base-model listings, retrieved 2026-09-11: $119,000 (1974, TT 16,005), $299,000 (1969, TT 5,024), $299,000 (1969, TT 8,361), $350,000 (1978, TT 2,586), $375,000 (1968, TT 17,528) and $475,000 (1981, TT 2,600). All six fall within this page's own year_range (1967-1984). The full survey is saved at raw/market/market-pa31-navajo-controller-2026-09-11.md.

The $475,000 listing may be a modified airframe, not a stock Navajo — it is listed by Mike Jones Aircraft Sales, the shop this page's own STCs & Modifications section names as the source of the Colemill/Panther conversion (re-engined, four-blade Q-Tip propellers, optional winglets), and its low total time (2,600) is consistent with a recently-converted airplane. This was not independently confirmed against the individual listing's equipment list this session, and is noted as a reason the top of the band may run high for a stock airplane.

price_min_usd: 119000, price_max_usd: 475000 (a 4.0x spread across 13 years of production and a genuine mix of stock and possibly-modified airframes — condition and equipment range, not evidence this page conflates several models). price_typical_usd: 325000 is the median of the six figures ($299,000 and $350,000 average to $324,500, rounded to $325,000), placed inside the observed band per rule 27 rather than asserted as an observed transaction price. Asking prices, not sold prices; dated 2026-09-11.

The base Navajo shares its airframe, fuel system and landing gear architecture with the Chieftain closely enough that most of the Chieftain page's AD and pre-buy discussion applies directly — see that page's ADs & Common Problems section for AD 2017-10-20 (fuselage bulkhead cracking, which explicitly names PA-31 serial ranges alongside PA-31-350's), AD 99-12-05 (elevator spar), AD 96-10-15 (wing attachment) and AD 80-18-10 (fuel selector valve) — all four apply by certificate-wide model list, not Chieftain-specific. The Navajo runs the same TIO-540 dual-magneto reliability profile discussed there, but with same-rotation (not counter-rotating) engines, so it does NOT get the Chieftain page's Vmc/critical-engine mitigation from opposite-rotation propellers — this airframe genuinely has a critical engine, and that is a real difference a transitioning pilot needs briefed, not a paperwork distinction.

See GA Insurance Underwriting and reference/insurance-costs.md, which records openly that the vault has no real insurance binder for any twin — its twin figures are extrapolated from BWI's published $4,000-$8,000 "complex/retractable single or twin" band, not anchored to an actual quote. Categorized heavy_twin_piston alongside the Chieftain on gross-weight proximity (6,500 lb against the Chieftain's 7,000 lb, both far closer to each other than to the PA-30 Twin Comanche's 3,600 lb "light_twin" tier) — a judgment call, not a citation, and no typical_hull_insurance_annual_usd is stored this session rather than invent a number the reference file itself says is unanchored.