Piper Aerostar 601P

The Aerostar is one of the fastest piston twins ever to enter series production and the only mid-wing, counter-rotating piston twin certified under FAR Part 23. Designed by Ted R. Smith — who also gave the world the Aero Commander — the Aerostar represents a philosophy of speed above all else. Its laminar-flow mid-wing and meticulously faired airframe achieve drag numbers that still embarrass contemporaries. The pressurized 601P, the most common variant, cruises faster than most turboprops at a fraction of the acquisition cost.

The aircraft has a complicated ownership history. Ted Smith Aircraft Company first flew a prototype in 1966 and began production in 1967. Ownership passed through American Cement Company, then Ted Smith and Associates, before Piper Aircraft acquired the line in 1978 and moved production to Vero Beach, Florida. Piper built the last Aerostar in 1984. In 1991, Piper sold the type certificate to Aerostar Aircraft Corporation (headed by Machen Inc. principals), which continues to provide factory support, service bulletins, and the Super 700 STC.

Approximately 1,010 Aerostars were built across all variants. The 601P is by far the most produced (492 units) and most commonly traded today. Ownership demands genuine multi-engine IFR currency, a fat maintenance budget, and ideally a relationship with a specialist shop. When flown by a proficient pilot, the Aerostar delivers speed that no piston twin can match: the 601P covers 1,000 nm stages routinely, and a Super 700 conversion pushes the cruise past 260 knots.

Notes on variant granularity: The 600A differs from the 600 only in minor detail; they share a page here. The 601B's wider wingspan was carried forward to all subsequent variants. The 602P is essentially a Piper-revised 601P with a factory-turbocharged engine assembly; performance is slightly lower than a well-maintained 601P but detonation risk is meaningfully reduced. The 700P and its STC clone, the Machen/Aerostar Aircraft Super 700, are the definitive high-performance Aerostars.

601P real-world cruise: Book figures show 257 KIAS max speed; realistic long-leg cruise at 75% power and 20,000–23,000 ft produces 230–240 KTAS burning 36–40 GPH total. At economy cruise (65%, 15,000 ft) expect 210–220 KTAS on 30–33 GPH. Block times are genuinely impressive: a 1,000 nm trip with a favorable FL that most piston aircraft cannot reach takes about 4.5 hours.

700P and Super 700: At 75% and 25,000 ft, the 700P/Super 700 trues at 255–265 KTAS on 48–51 GPH. Throttled to 55%, fuel burn drops to 32 GPH for 225 KTAS — a remarkable economy cruise that extends range to 1,100+ nm with max fuel.

600 naturally aspirated: The unpressurized 600A cruises 210 KTAS at 7,500 ft on 34 GPH — still fast for a piston twin, but without turbocharging the aircraft is altitude-constrained. Useful primarily for lower-altitude high-speed legs.

High wing loading: At 35.4 lbs/sq ft the Aerostar rides through convective turbulence better than lighter-loaded twins. The tradeoff is a narrow slow-speed envelope — Vs1 is 77 KIAS on the 601P; approach speeds are consequently higher than on comparable aircraft. Vref is typically around 100–105 KIAS. The high wing loading also causes the airplane to float in ground effect; disciplined approaches at the correct speed are essential.

Single-engine performance: Single-engine service ceiling (601P) is approximately 8,800 ft; single-engine climb rate is 240 FPM at sea level at max gross. The 700P improves this to approximately 320 FPM and 14,500 ft SE ceiling. These numbers are adequate but not generous; engine-out management after takeoff demands immediate, textbook procedure.

Pressurization: The 601P delivers a cabin altitude of approximately 11,000 ft at the 25,000 ft service ceiling (4.25 psi differential). The 602P and 700P are similar. Occupants benefit from a comfortable pressurized environment; the system is generally reliable but aging seals require ongoing attention.

Density altitude sensitivity: Both the naturally aspirated 600 and the turbocharged variants are affected by density altitude at takeoff. The turbocharged models maintain rated power to their critical altitude (approximately 18,000–20,000 ft) but high-elevation field departures at max gross weight should be planned carefully given the accelerate-stop distances.

The Aerostar 601P has a book useful load of approximately 1,944 lbs (6,000 lb gross minus 4,056 lb empty). However, real-world equipped useful load on a glass-panel, air-conditioned 601P is typically closer to 1,600–1,750 lbs after avionics, paint, interior, and equipment additions have accumulated.

Max fuel (165 gal = 990 lbs):

• Remaining payload after full fuel: 610–760 lbs
• Practical passengers: Pilot + 1 adult + moderate baggage; or pilot + 2 light adults, no bags
• Range at 75% (36 GPH): approximately 1,000–1,100 nm with 45-minute reserve
• This is the standard business travel configuration: maximum range, minimal payload

Full seats (6 x 190 lbs = 1,140 lbs occupants + 100 lbs baggage = 1,240 lbs):

• Fuel remaining after occupants/bags: 360–510 lbs (60–85 gallons)
• Range at 75% power: approximately 350–480 nm
• Practical range is severely limited with full occupancy; this configuration is occasionally viable for short hops

Practical sweet spot (pilot + 3 adults + baggage):

• Occupants + bags: ~850 lbs
• Available fuel: ~750–900 lbs (125–150 gallons)
• Range: 750–900 nm at 75% power
• This is the realistic working envelope for most mission profiles

700P / Super 700 (6,315–6,356 lb gross):

• Additional gross weight allowance of 315–356 lbs over the 601P improves all scenarios slightly
• With optional extended fuel (210 gal = 1,260 lbs), range at economy cruise (55%, 32 GPH) exceeds 1,300 nm
• At 75% power (51 GPH) with standard fuel (165 gal), range is approximately 868 nm

Important CG note: The Aerostar has a relatively narrow CG envelope. Weight and balance calculations are mandatory before every flight — not a formality. Particularly with variable fuel loads and passenger configurations, the CG can move to aft limits that significantly alter stall characteristics. The AD requiring stall modification (AD 83-14-7) was partially triggered by aft-CG accidents.

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Cross-references: valuation-methodology | insurance-underwriting | maintenance-ecosystem | avionics-pricing Related aircraft: piper-pa34-seneca | piper-pa30-twin-comanche | piper-pa23-apache-aztec

cross-country — Score: 9/10. The Aerostar's primary purpose. Speed, pressurization, long range (1,000+ nm with the 601P at economy cruise), and IFR capability combine to make this one of the best owner-flown cross-country platforms in piston aviation. The only demerits are high fuel burn and the complexity/maintenance cost of ownership. Pilots comfortable with the systems and currency requirements will find the Aerostar covers ground that a Beech Baron 58 or Piper Seneca simply cannot match.

business-travel — Score: 8/10. Fast, pressurized, and capable of flying above most weather make the Aerostar compelling for business travel. Six-seat configuration accommodates a pilot plus five passengers nominally, though useful load limitations in practice restrict full-fuel operations to pilot plus three to four adults. Cabin is narrow and not stand-up; it is not a corporate cabin but a very fast commuter. Requires a highly qualified pilot — most corporate operators use professional crew.

local-fun-flying — Score: 4/10. Technically possible but wasteful. High systems complexity, demanding handling characteristics, and significant cost-per-hour make casual local flying inadvisable and expensive. Best reserved for pilots maintaining currency through meaningful cross-country flying.

cargo-hauling — Score: 4/10. Useful load of ~1,600–1,900 lbs (depending on equipment and variant) is reasonable for light cargo, but the narrow cabin and door placement limit practical loading. Not a cargo hauler by design.

flight-training — Score: 1/10. Absolutely not a training aircraft. The Aerostar demands a fully current, experienced multi-engine IFR pilot. Its characteristics — high wing loading, critical engine-out margins, pressurization systems, narrow CG range — make it unsuitable for training environments. Transition training is required before first flight, but this is not the machine to build hours in.

aerobatics — Score: 1/10. Not aerobatic-certified. The mid-wing layout might suggest otherwise but the airframe, pressurization, and systems are entirely incompatible with aerobatic use.

backcountry-bush — Score: 1/10. High approach speeds, long accelerate-stop distances (3,100–4,000 ft), retractable gear with no ground clearance for unimproved surfaces, and zero STOL capability make the Aerostar completely unsuited to backcountry operations.

surveying — Score: 3/10. The speed and altitude capability could theoretically serve photogrammetric survey missions, but the fixed cabin windows, limited nose-down visibility, and high operating cost per hour make purpose-built survey platforms far more practical.

The Aerostar fleet spans 1967–1984 production, so panel configurations range from steam gauges with old autopilots to full glass. The type certificate supports modern STC-approved retrofits.

Entry-level (steam gauge, original): King KX-175/165 nav/comms, a KI-209 CDI, KT-76A transponder, and a vintage autopilot (S-TEC 60 or original Piper AutoControl). Functional for day/night VFR; the aircraft is IFR-capable but aging avionics make IFR currency difficult to maintain safely.

Mid-range modernized: Garmin GTN 650Xi or 750Xi as the primary navigator, replacing original nav/comms. A Garmin GI-275 or Aspen EFD1000 as a standby/backup ADI. Original autopilot retained. This is the most common upgrade tier — cost approximately $20,000–$35,000 installed — and provides WAAS GPS, ADS-B Out, and modern databases while keeping existing panel structure largely intact.

Full glass: Garmin G500 TXi (10.6" PFD + MFD) with GTN 750Xi navigator, GFC 500 or GFC 600 digital autopilot, GTX 345 ADS-B transceiver, and GMA 35 audio panel. Installation on an Aerostar runs $80,000–$120,000 depending on complexity and whether the autopilot is upgraded. Several shops have documented full glass Aerostar installations; Nexair Avionics (in at least one documented install) equipped a 601P with G500 TXi, GTX 345, and a GFC 600.

Autopilot note: The original Aerostar autopilot is functional when maintained, but aging servos and computers make overhauls expensive. An S-TEC 55X or Garmin GFC 500/600 retrofit provides considerably more capability (including GPS steering and altitude pre-select) and is strongly recommended for serious IFR operations.

ADS-B: ADS-B Out is required for the altitudes this aircraft flies. The Garmin GTX 345 or Garmin GTX 335 (Out only) are common solutions; installation is straightforward via GTN navigator integration.

Machen Super 700 / Aerostar Aircraft Super 700 STC The most significant modification available. Replaces the 601P or 602P's 290 HP TIO-540-S1A5 engines with 350 HP Lycoming TIO-540-U2A counter-rotating engines mated to three-blade Hartzell propellers. Gross weight increases to 6,356 lbs. Claimed 75% cruise: 261 KTAS. Initial climb: 1,875 FPM. Economy cruise at 55%: 225 KTAS at 32 GPH. This conversion essentially builds a 700P from a 601P. The STC is held by Aerostar Aircraft Corporation (successor to Machen Inc. after the 1991 TC acquisition). Installation cost: approximately $120,000–$150,000 depending on engine condition and shop. This is the recommended upgrade path for 601P owners planning long-term ownership; the counter-rotating engines eliminate critical engine concerns and the power increase provides meaningful single-engine margin improvement.

Machen Superstar 650 / 680 Conversions (historical) Earlier Machen conversions replaced engines with 325 HP (Superstar 650) or 340 HP intercooled (Superstar 680) engines. These conversions are no longer actively supported as a new STC but some examples exist in the fleet. Intercooling improved high-altitude cruise economy and reduced cylinder head temperatures. Performance falls between the stock 601P and the Super 700.

Aerostar Winglet STC Available from Aerostar Aircraft Corporation. Winglets improve cruise efficiency at high altitudes (roughly 3–5 knot cruise speed improvement) and improve single-engine climb rate slightly. Cost approximately $18,000–$25,000 installed.

Pressurization Door Seal Modification A widely adopted operator-developed STC replaces the original door pressure seals and routes pressurization through a dedicated electric pump rather than relying solely on the vacuum pump to maintain cabin pressure. This modification reduces vacuum pump wear and failure rate substantially. Approximately $3,000–$6,000 installed.

Speed Brake STC (various) Spoiler or speed brake installations have been STC'd on the Aerostar to provide descent speed control (the clean aircraft does not slow down quickly). Useful for arriving at busy airspace altitudes without power reductions that cool turbocharged engines rapidly.

See maintenance-ecosystem for the general framework. Aerostar-specific considerations:

A&P familiarity: Specialist. Most general aviation shops are uncomfortable with the Aerostar's turbocharged, pressurized, mid-wing systems. The aircraft's tightly packed systems are difficult to access. Owners strongly recommend establishing a relationship with a shop that has documented Aerostar experience before purchase. Aerostar Aircraft Corporation (Spokane, WA) remains the primary factory support organization and can refer qualified shops.

Annual inspection: A standard annual inspection runs 40–45 shop hours as a baseline. With typical discrepancies on an aging airframe, expect 60–80 hours of labor plus parts. Owner-reported annual costs range from $7,000 (clean aircraft, quick inspection) to $20,000+ when turbos, cylinders, or exhaust components need attention. Budget $12,000–$18,000/year as a realistic expectation for an actively flown 601P.

50-hour inspections: $500–$1,000 each occurrence; required by the engine manufacturer on turbocharged models.

Engine overhaul: Lycoming TIO-540-S1A5 (601P) TBO is 1,800 hours; field overhaul cost per engine approximately $28,000–$35,000 (factory reman from Lycoming approximately $40,000–$50,000 per side). Budget $60,000–$100,000 for a dual-engine overhaul event. The 700P's TIO-540-U2A carries the same 1,800-hour TBO at similar or slightly higher cost.

Exhaust system: The single most expensive recurring maintenance item outside of engines. Individual exhaust stacks, balance tubes, tailpipes, and wastegate components fail regularly on aging turbocharged aircraft. Budget $3,000–$8,000 per inspection event for exhaust work, and $15,000–$30,000 for a complete exhaust system replacement.

Turbocharger and wastegate: Turbocharger bearing replacement runs $3,000–$6,000 per side including labor. Wastegate controllers require periodic overhaul.

Pressurization seals and ducting: Door seals, window seals, and pressurization ducting degrade over time. A full reseal event can cost $8,000–$15,000. The recommended electric pump modification for door pressurization (see STCs section) reduces vacuum pump load and extends TBO intervals.

Vacuum pump: Pressurization-related cycling leads to accelerated vacuum pump wear. Budget for more frequent replacement than on non-pressurized aircraft unless the electric pump mod is installed.

Parts availability: Fair. Aerostar Aircraft Corporation maintains a parts inventory and is the primary source for OEM components. Some parts are no longer in production and require either NOS (new old stock) sourcing or serviceable used parts. Exhaust components are available through aftermarket suppliers (Plane Exhaust, Quality Aircraft Accessories). Lycoming engine parts are widely available through standard channels.

Owner community: The Aerostar Owners Association and associated forums (aerostar-owners.com) provide an active community for maintenance tips, shop referrals, and parts sourcing. This network is important for successful ownership.

Total annual ownership cost estimate (601P, 100 hours/year, mid-time engines):

• Fixed costs (insurance, hangar, annual): ~$20,000–$25,000
• Variable costs (fuel, oil, routine maintenance): ~$15,000–$18,000
• Reserve for major items (engine, exhaust, pressurization): ~$10,000–$15,000
• Total: approximately $45,000–$58,000/year

See valuation-methodology for the full framework. Aerostar-specific factors:

Model tier pricing (2025 approximate):

• 600/600A (naturally aspirated, unpressurized): $80,000–$180,000 depending on condition and avionics
• 601/601B (turbocharged, unpressurized): $100,000–$200,000
• 601P (pressurized, 290 HP): $150,000–$380,000
• 602P (Piper Sequoia): $160,000–$400,000
• 700P (factory 350 HP, 26 built): $350,000–$600,000+
• Super 700 conversion (601P/602P with 700P engines): $250,000–$500,000

Engine time: Dominates valuation. TBO is 1,800 hours for turbocharged variants. Fresh factory overhaul per side adds $28,000–$35,000 in direct cost and $50,000–$80,000 in perceived value. Mid-time engines (600–900 SMOH) command significant premiums over high-time or run-out engines. Always verify whether SMOH indicates factory new, field overhaul, or top overhaul — these are very different things on an aging turbo engine.

Exhaust system condition: A recently replaced or inspected exhaust system (within 100–200 hours) adds $10,000–$20,000 in effective value versus an aircraft with unknown or overdue exhaust.

Avionics: The Aerostar's speed and IFR capability are only realized with reliable modern navigation. A full Garmin GTN 750Xi + G500 TXi + GFC 600 installation adds $80,000–$120,000 in cost but arguably $60,000–$100,000 in value versus a steam-gauge aircraft. Buyers seeking to fly serious IFR should factor the cost of avionics upgrades when purchasing a steam-gauge example.

Super 700 conversion: Adds significant value — typically $80,000–$130,000 over a comparable unmodified 601P — and substantially changes the mission capability and single-engine safety margins. A well-documented Super 700 conversion with fresh engines is the most desirable configuration.

Total time airframe: Low-time airframes (under 3,000 hours) are preferred. Very high-time airframes (over 6,000–7,000 hours) require additional scrutiny of pressurization fittings, control cables, and structural components.

Logbooks and AD compliance: Complete, unbroken logbooks and documented compliance with all ADs and applicable service bulletins are essential to value. Missing logbook entries or undocumented compliance are major red flags and typically result in significant price discounts.

Critical Recurring ADs:

• AD 79-1-5: Fuel system — requires placarding crossfeed procedures and installation of a low-fuel warning light. Addresses single fuel pickups in the wing tanks that become unported in certain attitudes, potentially starving an engine when tanks are not balanced. Compliance is mandatory; compliance history should be verified at pre-buy.

• AD 83-14-7: Stall characteristics — requires aerodynamic stall improvement kit installation. The early Aerostar has sharp, abrupt stall behavior, particularly at aft CG. The AD mandates modification that softens the break. Verify installation on any aircraft pre-1984.

• AD 87-07-09: Exhaust system inspection — requires inspection of exhaust welds for cracks and pinholes, wastegate shaft/butterfly for heat distortion and freedom of movement, tailpipes for pitting/wall thickness, balance tube ports for cracks, and all slip joints. The turbocharged exhaust system runs extremely hot and is prone to cracking; a leaking exhaust system creates serious CO risk. This is a recurring inspection item.

• AD (2000-era): Elevator and aileron balance tube corrosion — repetitive inspection and replacement as required. A balance tube failure could cause control system jamming.

• AD (2002-era): Main landing gear lower side brace — cracking at the upper bolt lug. Inspection required; cracking is an airworthiness concern.

• AD (2003-era): Oil scavenge pump (Roto-Master/Rajay) — replacement with improved Aerostar scavenge pumps required. Affects 601P models with original turbocharger scavenge pumps.

• AD (2020-era): Continued structural inspections related to wing attachment fittings; SB600-136 also addresses visual inspection of wing attach fittings — at least one case of cracked left wing attachment fittings discovered during compliance.

Common Pre-Buy Red Flags:

• Fuel system corrosion: Aging wet wings can develop severe corrosion in the fuel tanks. One documented accident involved a double engine stoppage from fuel system corrosion blocking flow. Tank inspection is critical at pre-buy.
• Exhaust cracks: The turbocharged exhaust is the single biggest maintenance money pit. Inspect every exhaust component meticulously; replacement components are expensive (several hundred to several thousand dollars per section).
• Pressurization leaks: Rivet leaks in wet wings and deteriorating door seals are common on aircraft over 30 years old. Excessive compressor cycle frequency is a symptom. A pressurization leak check should be part of every pre-buy.
• Detonation damage (601P specifically): The TIO-540-S1A5 uses 8.7:1 compression and runs just below the detonation threshold in certain power/altitude/leaning combinations. Cylinders with detonation damage show bore scoring and reduced compression. A borescope inspection is mandatory at pre-buy.
• Nose gear fragility: The nose gear assembly is prone to damage from aggressive towing; collapsed nose gear on the ground is a known failure mode from improper handling. Inspect carefully.
• Alternator output: The 70-amp alternators produce only ~55 amps due to heat limitations. Verify both alternators are serviceable; the electrical load of modern avionics can be significant.
• Accident history: The Aerostar had a notably higher fatal accident rate than the Beech Baron 58 in early NTSB studies (4.4 vs. 1.4 per 100,000 hours in one period). Weather penetration, VMC loss, and fuel mismanagement dominate the accident record. Full airframe history research is essential.

Fuel mismanagement note: Jet A contamination accidents have occurred with the Aerostar. Clearly labeled avgas-only fuel caps and refueling vigilance are essential.

See insurance-underwriting for the general framework. Aerostar-specific considerations:

Underwriting category: The Aerostar is treated as a high-performance complex piston twin with above-average accident history. Underwriters scrutinize pilot qualifications heavily and typically require:

• Commercial or ATP certificate (some carriers accept instrument-rated private pilot with high experience)
• Minimum total time: 2,500 hours
• Minimum multi-engine time: 1,000 hours
• Minimum make/model time: 25 hours (some carriers require 50)
• Annual recurrent training with a qualified Aerostar instructor (documented)

Typical annual premiums (601P, $175,000–$250,000 hull value, $1,000,000 liability, 2021–2025 data):

• Qualified pilot (2,500+ TT, 1,000+ ME, 25+ make/model): $5,500–$8,200/year
• Less-qualified pilot (meeting minimums but lower experience): $9,850–$14,000/year
• 700P or Super 700 (higher hull value $350,000–$500,000): $8,000–$15,000/year

Training requirements: Most underwriters will not bind coverage without documented completion of an Aerostar-specific initial training course from a recognized provider. Pilots of America discussion forums and the AOPA Aerostar Owner community recommend annual recurrent training as a condition of coverage; many carriers require it annually.

Liability only (no hull): $750–$1,120/year for qualified pilots. Not recommended for aircraft with meaningful market value.

Key underwriting risk factors: History of instrument meteorological conditions accidents, turbocharged engine complexity, high wing loading (demanding stall/spin characteristics), and the aircraft's historical accident rate all contribute to elevated premiums relative to more docile piston twins.