# Wright XRJ47

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Wright_XRJ47
> Markdown URL: https://mediated.wiki/source/Wright_XRJ47.md
> Source: https://en.wikipedia.org/wiki/Wright_XRJ47
> Source revision: 1321553158
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

1950s American ramjet engine

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) This article needs more citations. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Wright XRJ47" – news · newspapers · books · scholar · JSTOR (November 2018) (Learn how and when to remove this message) This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (October 2018) (Learn how and when to remove this message) (Learn how and when to remove this message)

XRJ47 Type Ramjet National origin United States Manufacturer Wright Aeronautical

The **Wright XRJ47** was an American ramjet engine developed in the 1950s to help propel the rocket-launched [SM-64 Navaho](/source/SM-64_Navaho) supersonic intercontinental cruise missile. Although the design flight Mach Number was 2.75, a peak flight speed of Mach 3.0, at altitudes up to about 77,000 ft, was envisaged. This very large ramjet had a number of design problems, including some difficulty in light-up. Development of the Navaho missile was cancelled along with the ramjet engine in 1957.

## Design

The single cone supersonic intake supplied ram air to a long annular diffuser terminating at the aft-mounted cylindrical combustion chamber. The centreline of the intake system was gently curved, presumably to line up the intake face with the flow-field of the missile nose section.

The combustion chamber flame-holder consisted of a center-body pilot region, with three annular V-gutters interconnected by slanted radial V-gutters. Fuel jets were of variable area design.

A heat-shield, with multiple exit ports, provided cooling air for the jetpipe and the fixed area ratio convergent-divergent propelling nozzle. The exit diameter of the nozzle equaled that of the combustion chamber.

## Specifications (XRJ47-W-5)

*Data from* Aircraft Engine Characteristics Summary: Ram-jet XRJ47-W-5,[1] Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75[2]

#### General characteristics

- Type: Ramjet

- Length: 390 in (9,900 mm) combustion chamber plus ducting and diffuser

- Diameter: 48 in (1,200 mm) (combustion chamber)

- **Intake lip area:** 636 sq in (4,100 cm2)

- **Combustion chamber area:** 1,810 sq in (11,700 cm2)

- **Nozzle throat geometric area:** 1,182 sq in (7,630 cm2)

- **Nozzle exit geometric area:** 1,810 sq in (11,700 cm2)

- Dry weight: 1,011 lb (459 kg)

#### Components

- Compressor: Ramjet inlet/diffuser

- [Combustors](/source/Combustor): approx 1,887 K (2,937 °F; 1,614 °C)

- **Combustion efficiency:** 83.3%

- **Burn time:** 6500 s

- Fuel type: [JP-5](/source/JP-5) (F-44 / AVCAT)

#### Performance

- Maximum [thrust](/source/Thrust): 3,792 lbf (16.87 kN)

- Air mass flow: 59.8 lb/s (27.1 kg/s)

- Fuel consumption: 10,548 lb/h (4,784 kg/h)

- [Specific fuel consumption](/source/Thrust_specific_fuel_consumption): 2.782 lb/lbf/h (283.7 kg/kN/h)

- [Thrust-to-weight ratio](/source/Thrust-to-weight_ratio): 3.75

## References

1. **[^](#cite_ref-avialog_1-0)** [*Aircraft Engine Characteristics Summary: Ram-jet XRJ47-W-5*](https://www.avialogs.com/engines-w/wright/item/7729-xrj47-w-5-ramjet-aircraft-engine-characteristics-summary-1-april-1957). www.avialogs.com. 1957.

1. **[^](#cite_ref-NACA_2-0)** Welna, Henry J.; Reilly, Dwight H. (1955). [*Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75*](https://digital.library.unt.edu/ark:/67531/metadc53082/m2/1/high_res_d/19660027126.pdf) (PDF). Lewis Flight Propulsion Laboratory, Cleveland, Ohio.

## Further reading

- Arrighi, Robert S. (2016). *Bringing the Future Within Reach: Celebrating 75 Years of the NASA*. NASA.

v t e Wright and Lawrance aircraft engines Wright inline engines E Gipsy L-320 T-1 Tornado T-2 Tornado T-3 Tornado T-4 Tornado V-720 IV-1460 IV-1560 V-1950 Lawrance radials A-3 C-2 J-1 J-2 L-1 L-2 L-3 L-4 L-5 Wright radials Whirlwind family J-3 J-4 J-5 J-6-5 J-6-7 J-6-9 R-540 R-760 R-790 R-975 R-1510 R-1670 Cyclone family Cyclone 7 Cyclone 9 Cyclone Twin Cyclone Duplex-Cyclone Cyclone 22 R-1300 R-1750 R-1820 R-2600 R-3350 R-4090 Others L-3 Gale R-1200 R-2160 Tornado Turbojets J59 J61 J65 J67 Turboprops/turboshafts T35 T49 Ramjets RJ47 RJ55

v t e United States military ramjet, pulsejet, and scramjet aircraft engine designation system Ramjets RJ30 RJ31 RJ34 RJ35 RJ37 RJ39 RJ40 RJ41 RJ43 RJ45 RJ47 RJ49 RJ51 RJ55 RJ57 RJ59 Pulsejets PJ31 PJ32 PJ33 PJ35 PJ37 PJ39 PJ40 PJ42 PJ46 PJ49 Scramjets SJ61

---
Adapted from the Wikipedia article [Wright XRJ47](https://en.wikipedia.org/wiki/Wright_XRJ47) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Wright_XRJ47?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.