About Glide Phase Interceptor (GPI) Project:
- It is a missile-intercepting system under joint development by the US and Japan.
- By the end of 2032, Washington and Tokyo aim to achieve full operational capability for the system.
- What is the Glide Phase?
- With a traditional Intercontinental Ballistic Missile (ICBM), the warhead separates from its booster and continues on a parabolic, gravity driven trajectory to its target.
- A hypersonic weapon, by contrast, separates from its booster after the peak of its trajectory and accelerates toward the Earth using gravity. It then performs a pitch manoeuvre to begin a flatter trajectorycalled the glide phase.
- Unlike typical ballistic missiles, the hypersonic and glide vehicles travel at five times (or more) the speed of sound on an unpredictable trajectory.
- What is the Project all about?
- Hypersonic weapons or missiles pose a unique challenge due to their blinding speeds and relatively low altitudes (20 to 80 km) during the glide phase.
- They can navigate around areas containing known missile defence sensors.
- These characteristics make it particularly challenging for ground-based radar systems to track them efficiently.
- The GPI Project aims to provide regional hypersonic missile defence.
- It will achieve this by launching specially modified missiles from surface warships.
- These missiles will engage and destroy incominghypersonic missilesas they glide through the boundary between space and Earth’s atmosphere.
- The “glide” phase of the missile’s trajectory provides the best opportunityto intercept it before it enters its last high-speed drop.
Q1: What is an intercontinental ballistic missile (ICBM)?
An ICBM is a guided missile that is designed to deliver nuclear warheads, although it could also deliver other payloads. According to the Federation of American Scientists, ICBMs have a minimum range of 5,500 kilometers (3,400 miles), with maximum ranges varying from 7,000 to 16,000 kilometers. ICBMs are much faster and have a greater range than other types of ballistic missiles. Agni-V is an Indian ICBM with a range of over 5,000 km.
Source: Explained: What is the Glide Phase Interceptor (GPI) programme?
Last updated on July, 2026
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